Merge WebKit at r75315: Initial merge by git.

Change-Id: I570314b346ce101c935ed22a626b48c2af266b84

1 files changed, 3428 insertions, 0 deletions

diff --git a/Source/WebCore/rendering/RenderBox.cpp b/Source/WebCore/rendering/RenderBox.cpp
new file mode 100644
index 0000000..355d385
--- /dev/null
+++ b/Source/WebCore/rendering/RenderBox.cpp
@@ -0,0 +1,3428 @@
+/*
+ * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
+ *           (C) 1999 Antti Koivisto (koivisto@kde.org)
+ *           (C) 2005 Allan Sandfeld Jensen (kde@carewolf.com)
+ *           (C) 2005, 2006 Samuel Weinig (sam.weinig@gmail.com)
+ * Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010 Apple Inc. All rights reserved.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Library General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public License
+ * along with this library; see the file COPYING.LIB.  If not, write to
+ * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+ * Boston, MA 02110-1301, USA.
+ *
+ */
+
+#include "config.h"
+#include "RenderBox.h"
+
+#include "CachedImage.h"
+#include "Chrome.h"
+#include "ChromeClient.h"
+#include "Document.h"
+#include "FrameView.h"
+#include "GraphicsContext.h"
+#include "HitTestResult.h"
+#include "htmlediting.h"
+#include "HTMLElement.h"
+#include "HTMLNames.h"
+#include "ImageBuffer.h"
+#include "FloatQuad.h"
+#include "Frame.h"
+#include "Page.h"
+#if PLATFORM(ANDROID)
+#include "PlatformBridge.h"
+#endif
+#include "RenderArena.h"
+#include "RenderFlexibleBox.h"
+#include "RenderInline.h"
+#include "RenderLayer.h"
+#include "RenderTableCell.h"
+#include "RenderTheme.h"
+#ifdef ANDROID_LAYOUT
+#include "Settings.h"
+#endif
+#include "RenderView.h"
+#include "TransformState.h"
+#include <algorithm>
+#include <math.h>
+
+#if ENABLE(WML)
+#include "WMLNames.h"
+#endif
+
+using namespace std;
+
+namespace WebCore {
+
+using namespace HTMLNames;
+
+// Used by flexible boxes when flexing this element.
+typedef WTF::HashMap<const RenderBox*, int> OverrideSizeMap;
+static OverrideSizeMap* gOverrideSizeMap = 0;
+
+bool RenderBox::s_hadOverflowClip = false;
+
+RenderBox::RenderBox(Node* node)
+    : RenderBoxModelObject(node)
+    , m_marginLeft(0)
+    , m_marginRight(0)
+    , m_marginTop(0)
+    , m_marginBottom(0)
+    , m_minPreferredLogicalWidth(-1)
+    , m_maxPreferredLogicalWidth(-1)
+    , m_inlineBoxWrapper(0)
+#ifdef ANDROID_LAYOUT
+    , m_visibleWidth(0)
+    , m_isVisibleWidthChangedBeforeLayout(false)
+#endif
+{
+    setIsBox();
+}
+
+RenderBox::~RenderBox()
+{
+}
+
+int RenderBox::marginBefore() const
+{
+    switch (style()->writingMode()) {
+    case TopToBottomWritingMode:
+        return m_marginTop;
+    case BottomToTopWritingMode:
+        return m_marginBottom;
+    case LeftToRightWritingMode:
+        return m_marginLeft;
+    case RightToLeftWritingMode:
+        return m_marginRight;
+    }
+    ASSERT_NOT_REACHED();
+    return m_marginTop;
+}
+
+int RenderBox::marginAfter() const
+{
+    switch (style()->writingMode()) {
+    case TopToBottomWritingMode:
+        return m_marginBottom;
+    case BottomToTopWritingMode:
+        return m_marginTop;
+    case LeftToRightWritingMode:
+        return m_marginRight;
+    case RightToLeftWritingMode:
+        return m_marginLeft;
+    }
+    ASSERT_NOT_REACHED();
+    return m_marginBottom;
+}
+
+int RenderBox::marginStart() const
+{
+    if (style()->isHorizontalWritingMode())
+        return style()->isLeftToRightDirection() ? m_marginLeft : m_marginRight;
+    return style()->isLeftToRightDirection() ? m_marginTop : m_marginBottom;
+}
+
+int RenderBox::marginEnd() const
+{
+    if (style()->isHorizontalWritingMode())
+        return style()->isLeftToRightDirection() ? m_marginRight : m_marginLeft;
+    return style()->isLeftToRightDirection() ? m_marginBottom : m_marginTop;
+}
+
+void RenderBox::setMarginStart(int margin)
+{
+    if (style()->isHorizontalWritingMode()) {
+        if (style()->isLeftToRightDirection())
+            m_marginLeft = margin;
+        else
+            m_marginRight = margin;
+    } else {
+        if (style()->isLeftToRightDirection())
+            m_marginTop = margin;
+        else
+            m_marginBottom = margin;
+    }
+}
+
+void RenderBox::setMarginEnd(int margin)
+{
+    if (style()->isHorizontalWritingMode()) {
+        if (style()->isLeftToRightDirection())
+            m_marginRight = margin;
+        else
+            m_marginLeft = margin;
+    } else {
+        if (style()->isLeftToRightDirection())
+            m_marginBottom = margin;
+        else
+            m_marginTop = margin;
+    }
+}
+
+void RenderBox::setMarginBefore(int margin)
+{
+    switch (style()->writingMode()) {
+    case TopToBottomWritingMode:
+        m_marginTop = margin;
+        break;
+    case BottomToTopWritingMode:
+        m_marginBottom = margin;
+        break;
+    case LeftToRightWritingMode:
+        m_marginLeft = margin;
+        break;
+    case RightToLeftWritingMode:
+        m_marginRight = margin;
+        break;
+    }
+}
+
+void RenderBox::setMarginAfter(int margin)
+{
+    switch (style()->writingMode()) {
+    case TopToBottomWritingMode:
+        m_marginBottom = margin;
+        break;
+    case BottomToTopWritingMode:
+        m_marginTop = margin;
+        break;
+    case LeftToRightWritingMode:
+        m_marginRight = margin;
+        break;
+    case RightToLeftWritingMode:
+        m_marginLeft = margin;
+        break;
+    }
+}
+
+void RenderBox::destroy()
+{
+    // A lot of the code in this function is just pasted into
+    // RenderWidget::destroy. If anything in this function changes,
+    // be sure to fix RenderWidget::destroy() as well.
+    if (hasOverrideSize())
+        gOverrideSizeMap->remove(this);
+
+    if (style() && (style()->height().isPercent() || style()->minHeight().isPercent() || style()->maxHeight().isPercent()))
+        RenderBlock::removePercentHeightDescendant(this);
+
+    RenderBoxModelObject::destroy();
+}
+
+void RenderBox::removeFloatingOrPositionedChildFromBlockLists()
+{
+    ASSERT(isFloatingOrPositioned());
+
+    if (documentBeingDestroyed())
+        return;
+
+    if (isFloating()) {
+        RenderBlock* outermostBlock = containingBlock();
+        for (RenderBlock* p = outermostBlock; p && !p->isRenderView(); p = p->containingBlock()) {
+            if (p->containsFloat(this))
+                outermostBlock = p;
+        }
+
+        if (outermostBlock) {
+            RenderObject* parent = outermostBlock->parent();
+            if (parent && parent->isFlexibleBox())
+                outermostBlock = toRenderBlock(parent);
+
+            outermostBlock->markAllDescendantsWithFloatsForLayout(this, false);
+        }
+    }
+
+    if (isPositioned()) {
+        RenderObject* p;
+        for (p = parent(); p; p = p->parent()) {
+            if (p->isRenderBlock())
+                toRenderBlock(p)->removePositionedObject(this);
+        }
+    }
+}
+
+void RenderBox::styleWillChange(StyleDifference diff, const RenderStyle* newStyle)
+{
+    s_hadOverflowClip = hasOverflowClip();
+
+    if (style()) {
+        // The background of the root element or the body element could propagate up to
+        // the canvas.  Just dirty the entire canvas when our style changes substantially.
+        if (diff >= StyleDifferenceRepaint && node() &&
+                (node()->hasTagName(htmlTag) || node()->hasTagName(bodyTag)))
+            view()->repaint();
+        
+        // When a layout hint happens and an object's position style changes, we have to do a layout
+        // to dirty the render tree using the old position value now.
+        if (diff == StyleDifferenceLayout && parent() && style()->position() != newStyle->position()) {
+            markContainingBlocksForLayout();
+            if (style()->position() == StaticPosition)
+                repaint();
+            else if (newStyle->position() == AbsolutePosition || newStyle->position() == FixedPosition)
+                parent()->setChildNeedsLayout(true);
+            if (isFloating() && !isPositioned() && (newStyle->position() == AbsolutePosition || newStyle->position() == FixedPosition))
+                removeFloatingOrPositionedChildFromBlockLists();
+        }
+    } else if (newStyle && isBody())
+        view()->repaint();
+
+    if (FrameView *frameView = view()->frameView()) {
+        bool newStyleIsFixed = newStyle && newStyle->position() == FixedPosition;
+        bool oldStyleIsFixed = style() && style()->position() == FixedPosition;
+        if (newStyleIsFixed != oldStyleIsFixed) {
+            if (newStyleIsFixed)
+                frameView->addFixedObject();
+            else
+                frameView->removeFixedObject();
+        }
+    }
+
+    RenderBoxModelObject::styleWillChange(diff, newStyle);
+}
+
+void RenderBox::styleDidChange(StyleDifference diff, const RenderStyle* oldStyle)
+{
+    RenderBoxModelObject::styleDidChange(diff, oldStyle);
+
+    if (needsLayout() && oldStyle && (oldStyle->height().isPercent() || oldStyle->minHeight().isPercent() || oldStyle->maxHeight().isPercent()))
+        RenderBlock::removePercentHeightDescendant(this);
+
+    // If our zoom factor changes and we have a defined scrollLeft/Top, we need to adjust that value into the
+    // new zoomed coordinate space.
+    if (hasOverflowClip() && oldStyle && style() && oldStyle->effectiveZoom() != style()->effectiveZoom()) {
+        if (int left = layer()->scrollXOffset()) {
+            left = (left / oldStyle->effectiveZoom()) * style()->effectiveZoom();
+            layer()->scrollToXOffset(left);
+        }
+        if (int top = layer()->scrollYOffset()) {
+            top = (top / oldStyle->effectiveZoom()) * style()->effectiveZoom();
+            layer()->scrollToYOffset(top);
+        }
+    }
+
+    bool isBodyRenderer = isBody();
+    bool isRootRenderer = isRoot();
+
+    // Set the text color if we're the body.
+    if (isBodyRenderer)
+        document()->setTextColor(style()->visitedDependentColor(CSSPropertyColor));
+
+    if (isRootRenderer || isBodyRenderer) {
+        // Propagate the new writing mode and direction up to the RenderView.
+        RenderView* viewRenderer = view();
+        RenderStyle* viewStyle = viewRenderer->style();
+        if (viewStyle->direction() != style()->direction() && (isRootRenderer || !document()->directionSetOnDocumentElement())) {
+            viewStyle->setDirection(style()->direction());
+            if (isBodyRenderer)
+                document()->documentElement()->renderer()->style()->setDirection(style()->direction());
+            setNeedsLayoutAndPrefWidthsRecalc();
+        }
+
+        if (viewStyle->writingMode() != style()->writingMode() && (isRootRenderer || !document()->writingModeSetOnDocumentElement())) {
+            viewStyle->setWritingMode(style()->writingMode());
+            if (isBodyRenderer)
+                document()->documentElement()->renderer()->style()->setWritingMode(style()->writingMode());
+            setNeedsLayoutAndPrefWidthsRecalc();
+        }
+    }
+}
+
+void RenderBox::updateBoxModelInfoFromStyle()
+{
+    RenderBoxModelObject::updateBoxModelInfoFromStyle();
+
+    bool isRootObject = isRoot();
+    bool isViewObject = isRenderView();
+
+    // The root and the RenderView always paint their backgrounds/borders.
+    if (isRootObject || isViewObject)
+        setHasBoxDecorations(true);
+
+    setPositioned(style()->position() == AbsolutePosition || style()->position() == FixedPosition);
+    setFloating(!isPositioned() && style()->isFloating());
+
+    // We also handle <body> and <html>, whose overflow applies to the viewport.
+    if (style()->overflowX() != OVISIBLE && !isRootObject && (isRenderBlock() || isTableRow() || isTableSection())) {
+        bool boxHasOverflowClip = true;
+        if (isBody()) {
+            // Overflow on the body can propagate to the viewport under the following conditions.
+            // (1) The root element is <html>.
+            // (2) We are the primary <body> (can be checked by looking at document.body).
+            // (3) The root element has visible overflow.
+            if (document()->documentElement()->hasTagName(htmlTag) &&
+                document()->body() == node() &&
+                document()->documentElement()->renderer()->style()->overflowX() == OVISIBLE)
+                boxHasOverflowClip = false;
+        }
+        
+        // Check for overflow clip.
+        // It's sufficient to just check one direction, since it's illegal to have visible on only one overflow value.
+        if (boxHasOverflowClip) {
+            if (!s_hadOverflowClip)
+                // Erase the overflow
+                repaint();
+            setHasOverflowClip();
+        }
+    }
+
+    setHasTransform(style()->hasTransformRelatedProperty());
+    setHasReflection(style()->boxReflect());
+}
+
+void RenderBox::layout()
+{
+    ASSERT(needsLayout());
+
+    RenderObject* child = firstChild();
+    if (!child) {
+        setNeedsLayout(false);
+        return;
+    }
+
+    LayoutStateMaintainer statePusher(view(), this, IntSize(x(), y()), style()->isFlippedBlocksWritingMode());
+    while (child) {
+        child->layoutIfNeeded();
+        ASSERT(!child->needsLayout());
+        child = child->nextSibling();
+    }
+    statePusher.pop();
+    setNeedsLayout(false);
+}
+
+// More IE extensions.  clientWidth and clientHeight represent the interior of an object
+// excluding border and scrollbar.
+int RenderBox::clientWidth() const
+{
+    return width() - borderLeft() - borderRight() - verticalScrollbarWidth();
+}
+
+int RenderBox::clientHeight() const
+{
+    return height() - borderTop() - borderBottom() - horizontalScrollbarHeight();
+}
+
+int RenderBox::scrollWidth() const
+{
+    if (hasOverflowClip())
+        return layer()->scrollWidth();
+    // For objects with visible overflow, this matches IE.
+    // FIXME: Need to work right with writing modes.
+    if (style()->isLeftToRightDirection())
+        return max(clientWidth(), rightLayoutOverflow() - borderLeft());
+    return clientWidth() - min(0, leftLayoutOverflow() - borderLeft());
+}
+
+int RenderBox::scrollHeight() const
+{
+    if (hasOverflowClip())
+        return layer()->scrollHeight();
+    // For objects with visible overflow, this matches IE.
+    // FIXME: Need to work right with writing modes.
+    return max(clientHeight(), bottomLayoutOverflow() - borderTop());
+}
+
+int RenderBox::scrollLeft() const
+{
+    return hasOverflowClip() ? layer()->scrollXOffset() : 0;
+}
+
+int RenderBox::scrollTop() const
+{
+    return hasOverflowClip() ? layer()->scrollYOffset() : 0;
+}
+
+void RenderBox::setScrollLeft(int newLeft)
+{
+    if (hasOverflowClip())
+        layer()->scrollToXOffset(newLeft);
+}
+
+void RenderBox::setScrollTop(int newTop)
+{
+    if (hasOverflowClip())
+        layer()->scrollToYOffset(newTop);
+}
+
+void RenderBox::absoluteRects(Vector<IntRect>& rects, int tx, int ty)
+{
+    rects.append(IntRect(tx, ty, width(), height()));
+}
+
+void RenderBox::absoluteQuads(Vector<FloatQuad>& quads)
+{
+    quads.append(localToAbsoluteQuad(FloatRect(0, 0, width(), height())));
+}
+
+void RenderBox::updateLayerTransform()
+{
+    // Transform-origin depends on box size, so we need to update the layer transform after layout.
+    if (hasLayer())
+        layer()->updateTransform();
+}
+
+IntRect RenderBox::absoluteContentBox() const
+{
+    IntRect rect = contentBoxRect();
+    FloatPoint absPos = localToAbsolute(FloatPoint());
+    rect.move(absPos.x(), absPos.y());
+    return rect;
+}
+
+FloatQuad RenderBox::absoluteContentQuad() const
+{
+    IntRect rect = contentBoxRect();
+    return localToAbsoluteQuad(FloatRect(rect));
+}
+
+IntRect RenderBox::outlineBoundsForRepaint(RenderBoxModelObject* repaintContainer, IntPoint* cachedOffsetToRepaintContainer) const
+{
+    IntRect box = borderBoundingBox();
+    adjustRectForOutlineAndShadow(box);
+
+    FloatQuad containerRelativeQuad = FloatRect(box);
+    if (cachedOffsetToRepaintContainer)
+        containerRelativeQuad.move(cachedOffsetToRepaintContainer->x(), cachedOffsetToRepaintContainer->y());
+    else
+        containerRelativeQuad = localToContainerQuad(containerRelativeQuad, repaintContainer);
+
+    box = containerRelativeQuad.enclosingBoundingBox();
+
+    // FIXME: layoutDelta needs to be applied in parts before/after transforms and
+    // repaint containers. https://bugs.webkit.org/show_bug.cgi?id=23308
+    box.move(view()->layoutDelta());
+
+    return box;
+}
+
+void RenderBox::addFocusRingRects(Vector<IntRect>& rects, int tx, int ty)
+{
+    if (width() && height())
+        rects.append(IntRect(tx, ty, width(), height()));
+}
+
+IntRect RenderBox::reflectionBox() const
+{
+    IntRect result;
+    if (!style()->boxReflect())
+        return result;
+    IntRect box = borderBoxRect();
+    result = box;
+    switch (style()->boxReflect()->direction()) {
+        case ReflectionBelow:
+            result.move(0, box.height() + reflectionOffset());
+            break;
+        case ReflectionAbove:
+            result.move(0, -box.height() - reflectionOffset());
+            break;
+        case ReflectionLeft:
+            result.move(-box.width() - reflectionOffset(), 0);
+            break;
+        case ReflectionRight:
+            result.move(box.width() + reflectionOffset(), 0);
+            break;
+    }
+    return result;
+}
+
+int RenderBox::reflectionOffset() const
+{
+    if (!style()->boxReflect())
+        return 0;
+    if (style()->boxReflect()->direction() == ReflectionLeft || style()->boxReflect()->direction() == ReflectionRight)
+        return style()->boxReflect()->offset().calcValue(borderBoxRect().width());
+    return style()->boxReflect()->offset().calcValue(borderBoxRect().height());
+}
+
+IntRect RenderBox::reflectedRect(const IntRect& r) const
+{
+    if (!style()->boxReflect())
+        return IntRect();
+
+    IntRect box = borderBoxRect();
+    IntRect result = r;
+    switch (style()->boxReflect()->direction()) {
+        case ReflectionBelow:
+            result.setY(box.bottom() + reflectionOffset() + (box.bottom() - r.bottom()));
+            break;
+        case ReflectionAbove:
+            result.setY(box.y() - reflectionOffset() - box.height() + (box.bottom() - r.bottom()));
+            break;
+        case ReflectionLeft:
+            result.setX(box.x() - reflectionOffset() - box.width() + (box.right() - r.right()));
+            break;
+        case ReflectionRight:
+            result.setX(box.right() + reflectionOffset() + (box.right() - r.right()));
+            break;
+    }
+    return result;
+}
+
+int RenderBox::verticalScrollbarWidth() const
+{
+    return includeVerticalScrollbarSize() ? layer()->verticalScrollbarWidth() : 0;
+}
+
+int RenderBox::horizontalScrollbarHeight() const
+{
+    return includeHorizontalScrollbarSize() ? layer()->horizontalScrollbarHeight() : 0;
+}
+
+bool RenderBox::scroll(ScrollDirection direction, ScrollGranularity granularity, float multiplier, Node** stopNode)
+{
+    RenderLayer* l = layer();
+    if (l && l->scroll(direction, granularity, multiplier)) {
+        if (stopNode)
+            *stopNode = node();
+        return true;
+    }
+
+    if (stopNode && *stopNode && *stopNode == node())
+        return true;
+
+    RenderBlock* b = containingBlock();
+    if (b && !b->isRenderView())
+        return b->scroll(direction, granularity, multiplier, stopNode);
+    return false;
+}
+
+bool RenderBox::logicalScroll(ScrollLogicalDirection direction, ScrollGranularity granularity, float multiplier, Node** stopNode)
+{
+    bool scrolled = false;
+    
+    RenderLayer* l = layer();
+    if (l) {
+#if PLATFORM(MAC)
+        // On Mac only we reset the inline direction position when doing a document scroll (e.g., hitting Home/End).
+        if (granularity == ScrollByDocument)
+            scrolled = l->scroll(logicalToPhysical(ScrollInlineDirectionBackward, style()->isHorizontalWritingMode(), style()->isFlippedBlocksWritingMode()), ScrollByDocument, multiplier);
+#endif
+        if (l->scroll(logicalToPhysical(direction, style()->isHorizontalWritingMode(), style()->isFlippedBlocksWritingMode()), granularity, multiplier))
+            scrolled = true;
+        
+        if (scrolled) {
+            if (stopNode)
+                *stopNode = node();
+            return true;
+        }
+    }
+
+    if (stopNode && *stopNode && *stopNode == node())
+        return true;
+
+    RenderBlock* b = containingBlock();
+    if (b && !b->isRenderView())
+        return b->logicalScroll(direction, granularity, multiplier, stopNode);
+    return false;
+}
+
+bool RenderBox::canBeScrolledAndHasScrollableArea() const
+{
+    return canBeProgramaticallyScrolled(false) && (scrollHeight() != clientHeight() || scrollWidth() != clientWidth());
+}
+    
+bool RenderBox::canBeProgramaticallyScrolled(bool) const
+{
+    return (hasOverflowClip() && (scrollsOverflow() || (node() && node()->isContentEditable()))) || (node() && node()->isDocumentNode());
+}
+
+void RenderBox::autoscroll()
+{
+    if (layer())
+        layer()->autoscroll();
+}
+
+void RenderBox::panScroll(const IntPoint& source)
+{
+    if (layer())
+        layer()->panScrollFromPoint(source);
+}
+
+int RenderBox::minPreferredLogicalWidth() const
+{
+    if (preferredLogicalWidthsDirty())
+        const_cast<RenderBox*>(this)->computePreferredLogicalWidths();
+        
+    return m_minPreferredLogicalWidth;
+}
+
+int RenderBox::maxPreferredLogicalWidth() const
+{
+    if (preferredLogicalWidthsDirty())
+        const_cast<RenderBox*>(this)->computePreferredLogicalWidths();
+        
+    return m_maxPreferredLogicalWidth;
+}
+
+int RenderBox::overrideSize() const
+{
+    if (!hasOverrideSize())
+        return -1;
+    return gOverrideSizeMap->get(this);
+}
+
+void RenderBox::setOverrideSize(int s)
+{
+    if (s == -1) {
+        if (hasOverrideSize()) {
+            setHasOverrideSize(false);
+            gOverrideSizeMap->remove(this);
+        }
+    } else {
+        if (!gOverrideSizeMap)
+            gOverrideSizeMap = new OverrideSizeMap();
+        setHasOverrideSize(true);
+        gOverrideSizeMap->set(this, s);
+    }
+}
+
+int RenderBox::overrideWidth() const
+{
+    return hasOverrideSize() ? overrideSize() : width();
+}
+
+int RenderBox::overrideHeight() const
+{
+    return hasOverrideSize() ? overrideSize() : height();
+}
+
+int RenderBox::computeBorderBoxLogicalWidth(int width) const
+{
+    int bordersPlusPadding = borderAndPaddingLogicalWidth();
+    if (style()->boxSizing() == CONTENT_BOX)
+        return width + bordersPlusPadding;
+    return max(width, bordersPlusPadding);
+}
+
+int RenderBox::computeBorderBoxLogicalHeight(int height) const
+{
+    int bordersPlusPadding = borderAndPaddingLogicalHeight();
+    if (style()->boxSizing() == CONTENT_BOX)
+        return height + bordersPlusPadding;
+    return max(height, bordersPlusPadding);
+}
+
+int RenderBox::computeContentBoxLogicalWidth(int width) const
+{
+    if (style()->boxSizing() == BORDER_BOX)
+        width -= borderAndPaddingLogicalWidth();
+    return max(0, width);
+}
+
+int RenderBox::computeContentBoxLogicalHeight(int height) const
+{
+    if (style()->boxSizing() == BORDER_BOX)
+        height -= borderAndPaddingLogicalHeight();
+    return max(0, height);
+}
+
+// Hit Testing
+bool RenderBox::nodeAtPoint(const HitTestRequest& request, HitTestResult& result, int xPos, int yPos, int tx, int ty, HitTestAction action)
+{
+    tx += x();
+    ty += y();
+
+    // Check kids first.
+    for (RenderObject* child = lastChild(); child; child = child->previousSibling()) {
+        if (!child->hasLayer() && child->nodeAtPoint(request, result, xPos, yPos, tx, ty, action)) {
+            updateHitTestResult(result, IntPoint(xPos - tx, yPos - ty));
+            return true;
+        }
+    }
+
+    // Check our bounds next. For this purpose always assume that we can only be hit in the
+    // foreground phase (which is true for replaced elements like images).
+    IntRect boundsRect = IntRect(tx, ty, width(), height());
+    if (visibleToHitTesting() && action == HitTestForeground && boundsRect.intersects(result.rectForPoint(xPos, yPos))) {
+        updateHitTestResult(result, IntPoint(xPos - tx, yPos - ty));
+        if (!result.addNodeToRectBasedTestResult(node(), xPos, yPos, boundsRect))
+            return true;
+    }
+
+    return false;
+}
+
+// --------------------- painting stuff -------------------------------
+
+void RenderBox::paint(PaintInfo& paintInfo, int tx, int ty)
+{
+    tx += x();
+    ty += y();
+
+    // default implementation. Just pass paint through to the children
+    PaintInfo childInfo(paintInfo);
+    childInfo.updatePaintingRootForChildren(this);
+    for (RenderObject* child = firstChild(); child; child = child->nextSibling())
+        child->paint(childInfo, tx, ty);
+}
+
+void RenderBox::paintRootBoxDecorations(PaintInfo& paintInfo, int tx, int ty)
+{
+    const FillLayer* bgLayer = style()->backgroundLayers();
+    Color bgColor = style()->visitedDependentColor(CSSPropertyBackgroundColor);
+    RenderObject* bodyObject = 0;
+    if (!hasBackground() && node() && node()->hasTagName(HTMLNames::htmlTag)) {
+        // Locate the <body> element using the DOM.  This is easier than trying
+        // to crawl around a render tree with potential :before/:after content and
+        // anonymous blocks created by inline <body> tags etc.  We can locate the <body>
+        // render object very easily via the DOM.
+        HTMLElement* body = document()->body();
+        bodyObject = (body && body->hasLocalName(bodyTag)) ? body->renderer() : 0;
+        if (bodyObject) {
+            bgLayer = bodyObject->style()->backgroundLayers();
+            bgColor = bodyObject->style()->visitedDependentColor(CSSPropertyBackgroundColor);
+        }
+    }
+
+    // The background of the box generated by the root element covers the entire canvas, so just use
+    // the RenderView's docTop/Left/Width/Height accessors.
+    paintFillLayers(paintInfo, bgColor, bgLayer, view()->docLeft(), view()->docTop(), view()->docWidth(), view()->docHeight(), CompositeSourceOver, bodyObject);
+
+    if (style()->hasBorder() && style()->display() != INLINE)
+        paintBorder(paintInfo.context, tx, ty, width(), height(), style());
+}
+
+void RenderBox::paintBoxDecorations(PaintInfo& paintInfo, int tx, int ty)
+{
+    if (!paintInfo.shouldPaintWithinRoot(this))
+        return;
+
+    if (isRoot()) {
+        paintRootBoxDecorations(paintInfo, tx, ty);
+        return;
+    }
+
+    return paintBoxDecorationsWithSize(paintInfo, tx, ty, width(), height());
+}
+
+void RenderBox::paintBoxDecorationsWithSize(PaintInfo& paintInfo, int tx, int ty, int width, int height)
+{
+    // border-fit can adjust where we paint our border and background.  If set, we snugly fit our line box descendants.  (The iChat
+    // balloon layout is an example of this).
+    borderFitAdjust(tx, width);
+
+    // FIXME: Should eventually give the theme control over whether the box shadow should paint, since controls could have
+    // custom shadows of their own.
+    paintBoxShadow(paintInfo.context, tx, ty, width, height, style(), Normal);
+
+    // If we have a native theme appearance, paint that before painting our background.
+    // The theme will tell us whether or not we should also paint the CSS background.
+    bool themePainted = style()->hasAppearance() && !theme()->paint(this, paintInfo, IntRect(tx, ty, width, height));
+    if (!themePainted) {
+        // The <body> only paints its background if the root element has defined a background
+        // independent of the body.  Go through the DOM to get to the root element's render object,
+        // since the root could be inline and wrapped in an anonymous block.
+        if (!isBody() || document()->documentElement()->renderer()->hasBackground())
+            paintFillLayers(paintInfo, style()->visitedDependentColor(CSSPropertyBackgroundColor), style()->backgroundLayers(), tx, ty, width, height);
+        if (style()->hasAppearance())
+            theme()->paintDecorations(this, paintInfo, IntRect(tx, ty, width, height));
+    }
+    paintBoxShadow(paintInfo.context, tx, ty, width, height, style(), Inset);
+
+    // The theme will tell us whether or not we should also paint the CSS border.
+    if ((!style()->hasAppearance() || (!themePainted && theme()->paintBorderOnly(this, paintInfo, IntRect(tx, ty, width, height)))) && style()->hasBorder())
+        paintBorder(paintInfo.context, tx, ty, width, height, style());
+}
+
+void RenderBox::paintMask(PaintInfo& paintInfo, int tx, int ty)
+{
+    if (!paintInfo.shouldPaintWithinRoot(this) || style()->visibility() != VISIBLE || paintInfo.phase != PaintPhaseMask || paintInfo.context->paintingDisabled())
+        return;
+
+    int w = width();
+    int h = height();
+
+    // border-fit can adjust where we paint our border and background.  If set, we snugly fit our line box descendants.  (The iChat
+    // balloon layout is an example of this).
+    borderFitAdjust(tx, w);
+
+    paintMaskImages(paintInfo, tx, ty, w, h);
+}
+
+void RenderBox::paintMaskImages(const PaintInfo& paintInfo, int tx, int ty, int w, int h)
+{
+    // Figure out if we need to push a transparency layer to render our mask.
+    bool pushTransparencyLayer = false;
+    bool compositedMask = hasLayer() && layer()->hasCompositedMask();
+    CompositeOperator compositeOp = CompositeSourceOver;
+
+    bool allMaskImagesLoaded = true;
+    
+    if (!compositedMask) {
+        // If the context has a rotation, scale or skew, then use a transparency layer to avoid
+        // pixel cruft around the edge of the mask.
+        const AffineTransform& currentCTM = paintInfo.context->getCTM();
+        pushTransparencyLayer = !currentCTM.isIdentityOrTranslationOrFlipped();
+
+        StyleImage* maskBoxImage = style()->maskBoxImage().image();
+        const FillLayer* maskLayers = style()->maskLayers();
+
+        // Don't render a masked element until all the mask images have loaded, to prevent a flash of unmasked content.
+        if (maskBoxImage)
+            allMaskImagesLoaded &= maskBoxImage->isLoaded();
+
+        if (maskLayers)
+            allMaskImagesLoaded &= maskLayers->imagesAreLoaded();
+
+        // Before all images have loaded, just use an empty transparency layer as the mask.
+        if (!allMaskImagesLoaded)
+            pushTransparencyLayer = true;
+
+        if (maskBoxImage && maskLayers->hasImage()) {
+            // We have a mask-box-image and mask-image, so need to composite them together before using the result as a mask.
+            pushTransparencyLayer = true;
+        } else {
+            // We have to use an extra image buffer to hold the mask. Multiple mask images need
+            // to composite together using source-over so that they can then combine into a single unified mask that
+            // can be composited with the content using destination-in.  SVG images need to be able to set compositing modes
+            // as they draw images contained inside their sub-document, so we paint all our images into a separate buffer
+            // and composite that buffer as the mask.
+            // We have to check that the mask images to be rendered contain at least one image that can be actually used in rendering
+            // before pushing the transparency layer.
+            for (const FillLayer* fillLayer = maskLayers->next(); fillLayer; fillLayer = fillLayer->next()) {
+                if (fillLayer->hasImage() && fillLayer->image()->canRender(style()->effectiveZoom())) {
+                    pushTransparencyLayer = true;
+                    // We found one image that can be used in rendering, exit the loop
+                    break;
+                }
+            }
+        }
+        
+        compositeOp = CompositeDestinationIn;
+        if (pushTransparencyLayer) {
+            paintInfo.context->setCompositeOperation(CompositeDestinationIn);
+            paintInfo.context->beginTransparencyLayer(1.0f);
+            compositeOp = CompositeSourceOver;
+        }
+    }
+
+    if (allMaskImagesLoaded) {
+        paintFillLayers(paintInfo, Color(), style()->maskLayers(), tx, ty, w, h, compositeOp);
+        paintNinePieceImage(paintInfo.context, tx, ty, w, h, style(), style()->maskBoxImage(), compositeOp);
+    }
+    
+    if (pushTransparencyLayer)
+        paintInfo.context->endTransparencyLayer();
+}
+
+IntRect RenderBox::maskClipRect()
+{
+    IntRect bbox = borderBoxRect();
+    if (style()->maskBoxImage().image())
+        return bbox;
+    
+    IntRect result;
+    for (const FillLayer* maskLayer = style()->maskLayers(); maskLayer; maskLayer = maskLayer->next()) {
+        if (maskLayer->image()) {
+            IntRect maskRect;
+            IntPoint phase;
+            IntSize tileSize;
+            calculateBackgroundImageGeometry(maskLayer, bbox.x(), bbox.y(), bbox.width(), bbox.height(), maskRect, phase, tileSize);
+            result.unite(maskRect);
+        }
+    }
+    return result;
+}
+
+void RenderBox::paintFillLayers(const PaintInfo& paintInfo, const Color& c, const FillLayer* fillLayer, int tx, int ty, int width, int height, CompositeOperator op, RenderObject* backgroundObject)
+{
+    if (!fillLayer)
+        return;
+
+    paintFillLayers(paintInfo, c, fillLayer->next(), tx, ty, width, height, op, backgroundObject);
+    paintFillLayer(paintInfo, c, fillLayer, tx, ty, width, height, op, backgroundObject);
+}
+
+void RenderBox::paintFillLayer(const PaintInfo& paintInfo, const Color& c, const FillLayer* fillLayer, int tx, int ty, int width, int height, CompositeOperator op, RenderObject* backgroundObject)
+{
+    paintFillLayerExtended(paintInfo, c, fillLayer, tx, ty, width, height, 0, op, backgroundObject);
+}
+
+#if USE(ACCELERATED_COMPOSITING)
+static bool layersUseImage(WrappedImagePtr image, const FillLayer* layers)
+{
+    for (const FillLayer* curLayer = layers; curLayer; curLayer = curLayer->next()) {
+        if (curLayer->image() && image == curLayer->image()->data())
+            return true;
+    }
+
+    return false;
+}
+#endif
+
+void RenderBox::imageChanged(WrappedImagePtr image, const IntRect*)
+{
+    if (!parent())
+        return;
+
+    if ((style()->borderImage().image() && style()->borderImage().image()->data() == image) ||
+        (style()->maskBoxImage().image() && style()->maskBoxImage().image()->data() == image)) {
+        repaint();
+        return;
+    }
+
+    bool didFullRepaint = repaintLayerRectsForImage(image, style()->backgroundLayers(), true);
+    if (!didFullRepaint)
+        repaintLayerRectsForImage(image, style()->maskLayers(), false);
+
+
+#if USE(ACCELERATED_COMPOSITING)
+    if (hasLayer() && layer()->hasCompositedMask() && layersUseImage(image, style()->maskLayers()))
+        layer()->contentChanged(RenderLayer::MaskImageChanged);
+#endif
+}
+
+bool RenderBox::repaintLayerRectsForImage(WrappedImagePtr image, const FillLayer* layers, bool drawingBackground)
+{
+    IntRect rendererRect;
+    RenderBox* layerRenderer = 0;
+
+    for (const FillLayer* curLayer = layers; curLayer; curLayer = curLayer->next()) {
+        if (curLayer->image() && image == curLayer->image()->data() && curLayer->image()->canRender(style()->effectiveZoom())) {
+            // Now that we know this image is being used, compute the renderer and the rect
+            // if we haven't already
+            if (!layerRenderer) {
+                bool drawingRootBackground = drawingBackground && (isRoot() || (isBody() && !document()->documentElement()->renderer()->hasBackground()));
+                if (drawingRootBackground) {
+                    layerRenderer = view();
+
+                    int rw;
+                    int rh;
+
+                    if (FrameView* frameView = toRenderView(layerRenderer)->frameView()) {
+                        rw = frameView->contentsWidth();
+                        rh = frameView->contentsHeight();
+                    } else {
+                        rw = layerRenderer->width();
+                        rh = layerRenderer->height();
+                    }
+                    rendererRect = IntRect(-layerRenderer->marginLeft(),
+                        -layerRenderer->marginTop(),
+                        max(layerRenderer->width() + layerRenderer->marginLeft() + layerRenderer->marginRight() + layerRenderer->borderLeft() + layerRenderer->borderRight(), rw),
+                        max(layerRenderer->height() + layerRenderer->marginTop() + layerRenderer->marginBottom() + layerRenderer->borderTop() + layerRenderer->borderBottom(), rh));
+                } else {
+                    layerRenderer = this;
+                    rendererRect = borderBoxRect();
+                }
+            }
+
+            IntRect repaintRect;
+            IntPoint phase;
+            IntSize tileSize;
+            layerRenderer->calculateBackgroundImageGeometry(curLayer, rendererRect.x(), rendererRect.y(), rendererRect.width(), rendererRect.height(), repaintRect, phase, tileSize);
+            layerRenderer->repaintRectangle(repaintRect);
+            if (repaintRect == rendererRect)
+                return true;
+        }
+    }
+    return false;
+}
+
+#if PLATFORM(MAC)
+
+void RenderBox::paintCustomHighlight(int tx, int ty, const AtomicString& type, bool behindText)
+{
+    Frame* frame = this->frame();
+    if (!frame)
+        return;
+    Page* page = frame->page();
+    if (!page)
+        return;
+
+    InlineBox* boxWrap = inlineBoxWrapper();
+    RootInlineBox* r = boxWrap ? boxWrap->root() : 0;
+    if (r) {
+        FloatRect rootRect(tx + r->x(), ty + r->selectionTop(), r->logicalWidth(), r->selectionHeight());
+        FloatRect imageRect(tx + x(), rootRect.y(), width(), rootRect.height());
+        page->chrome()->client()->paintCustomHighlight(node(), type, imageRect, rootRect, behindText, false);
+    } else {
+        FloatRect imageRect(tx + x(), ty + y(), width(), height());
+        page->chrome()->client()->paintCustomHighlight(node(), type, imageRect, imageRect, behindText, false);
+    }
+}
+
+#endif
+
+bool RenderBox::pushContentsClip(PaintInfo& paintInfo, int tx, int ty)
+{
+    if (paintInfo.phase == PaintPhaseBlockBackground || paintInfo.phase == PaintPhaseSelfOutline || paintInfo.phase == PaintPhaseMask)
+        return false;
+        
+    bool isControlClip = hasControlClip();
+    bool isOverflowClip = hasOverflowClip() && !layer()->isSelfPaintingLayer();
+    
+    if (!isControlClip && !isOverflowClip)
+        return false;
+    
+    if (paintInfo.phase == PaintPhaseOutline)
+        paintInfo.phase = PaintPhaseChildOutlines;
+    else if (paintInfo.phase == PaintPhaseChildBlockBackground) {
+        paintInfo.phase = PaintPhaseBlockBackground;
+        paintObject(paintInfo, tx, ty);
+        paintInfo.phase = PaintPhaseChildBlockBackgrounds;
+    }
+    IntRect clipRect(isControlClip ? controlClipRect(tx, ty) : overflowClipRect(tx, ty));
+    paintInfo.context->save();
+    if (style()->hasBorderRadius()) {
+        IntSize topLeft, topRight, bottomLeft, bottomRight;
+        IntRect borderRect = IntRect(tx, ty, width(), height());
+        style()->getBorderRadiiForRect(borderRect, topLeft, topRight, bottomLeft, bottomRight);
+
+        paintInfo.context->addRoundedRectClip(borderRect, topLeft, topRight, bottomLeft, bottomRight);
+    }
+    
+    paintInfo.context->clip(clipRect);
+    return true;
+}
+
+void RenderBox::popContentsClip(PaintInfo& paintInfo, PaintPhase originalPhase, int tx, int ty)
+{
+    ASSERT(hasControlClip() || (hasOverflowClip() && !layer()->isSelfPaintingLayer()));
+
+    paintInfo.context->restore();
+    if (originalPhase == PaintPhaseOutline) {
+        paintInfo.phase = PaintPhaseSelfOutline;
+        paintObject(paintInfo, tx, ty);
+        paintInfo.phase = originalPhase;
+    } else if (originalPhase == PaintPhaseChildBlockBackground)
+        paintInfo.phase = originalPhase;
+}
+
+IntRect RenderBox::overflowClipRect(int tx, int ty)
+{
+    // FIXME: When overflow-clip (CSS3) is implemented, we'll obtain the property
+    // here.
+
+    int bLeft = borderLeft();
+    int bTop = borderTop();
+
+    int clipX = tx + bLeft;
+    int clipY = ty + bTop;
+    int clipWidth = width() - bLeft - borderRight();
+    int clipHeight = height() - bTop - borderBottom();
+
+    // Subtract out scrollbars if we have them.
+    if (layer()) {
+        clipWidth -= layer()->verticalScrollbarWidth();
+        clipHeight -= layer()->horizontalScrollbarHeight();
+    }
+
+    return IntRect(clipX, clipY, clipWidth, clipHeight);
+}
+
+IntRect RenderBox::clipRect(int tx, int ty)
+{
+    int clipX = tx;
+    int clipY = ty;
+    int clipWidth = width();
+    int clipHeight = height();
+
+    if (!style()->clipLeft().isAuto()) {
+        int c = style()->clipLeft().calcValue(width());
+        clipX += c;
+        clipWidth -= c;
+    }
+
+    if (!style()->clipRight().isAuto())
+        clipWidth -= width() - style()->clipRight().calcValue(width());
+
+    if (!style()->clipTop().isAuto()) {
+        int c = style()->clipTop().calcValue(height());
+        clipY += c;
+        clipHeight -= c;
+    }
+
+    if (!style()->clipBottom().isAuto())
+        clipHeight -= height() - style()->clipBottom().calcValue(height());
+
+    return IntRect(clipX, clipY, clipWidth, clipHeight);
+}
+
+int RenderBox::containingBlockLogicalWidthForContent() const
+{
+    RenderBlock* cb = containingBlock();
+    if (shrinkToAvoidFloats())
+        return cb->availableLogicalWidthForLine(y(), false);
+    return cb->availableLogicalWidth();
+}
+
+int RenderBox::perpendicularContainingBlockLogicalHeight() const
+{
+    RenderBlock* cb = containingBlock();
+    RenderStyle* containingBlockStyle = cb->style();
+    Length logicalHeightLength = containingBlockStyle->logicalHeight();
+    
+    // FIXME: For now just support fixed heights.  Eventually should support percentage heights as well.
+    if (!logicalHeightLength.isFixed()) {
+        // Rather than making the child be completely unconstrained, WinIE uses the viewport width and height
+        // as a constraint.  We do that for now as well even though it's likely being unconstrained is what the spec
+        // will decide.
+        return containingBlockStyle->isHorizontalWritingMode() ? view()->frameView()->visibleHeight() : view()->frameView()->visibleWidth();
+    }
+    
+    // Use the content box logical height as specified by the style.
+    return cb->computeContentBoxLogicalHeight(logicalHeightLength.value());
+}
+
+void RenderBox::mapLocalToContainer(RenderBoxModelObject* repaintContainer, bool fixed, bool useTransforms, TransformState& transformState) const
+{
+    if (repaintContainer == this)
+        return;
+
+    if (RenderView* v = view()) {
+        if (v->layoutStateEnabled() && !repaintContainer) {
+            LayoutState* layoutState = v->layoutState();
+            IntSize offset = layoutState->m_paintOffset;
+            offset.expand(x(), y());
+            if (style()->position() == RelativePosition && layer())
+                offset += layer()->relativePositionOffset();
+            transformState.move(offset);
+            return;
+        }
+    }
+
+    bool containerSkipped;
+    RenderObject* o = container(repaintContainer, &containerSkipped);
+    if (!o)
+        return;
+
+    bool isFixedPos = style()->position() == FixedPosition;
+    bool hasTransform = hasLayer() && layer()->transform();
+    if (hasTransform) {
+        // If this box has a transform, it acts as a fixed position container for fixed descendants,
+        // and may itself also be fixed position. So propagate 'fixed' up only if this box is fixed position.
+        fixed &= isFixedPos;
+    } else
+        fixed |= isFixedPos;
+    
+    IntSize containerOffset = offsetFromContainer(o, roundedIntPoint(transformState.mappedPoint()));
+    
+    bool preserve3D = useTransforms && (o->style()->preserves3D() || style()->preserves3D());
+    if (useTransforms && shouldUseTransformFromContainer(o)) {
+        TransformationMatrix t;
+        getTransformFromContainer(o, containerOffset, t);
+        transformState.applyTransform(t, preserve3D ? TransformState::AccumulateTransform : TransformState::FlattenTransform);
+    } else
+        transformState.move(containerOffset.width(), containerOffset.height(), preserve3D ? TransformState::AccumulateTransform : TransformState::FlattenTransform);
+
+    if (containerSkipped) {
+        // There can't be a transform between repaintContainer and o, because transforms create containers, so it should be safe
+        // to just subtract the delta between the repaintContainer and o.
+        IntSize containerOffset = repaintContainer->offsetFromAncestorContainer(o);
+        transformState.move(-containerOffset.width(), -containerOffset.height(), preserve3D ? TransformState::AccumulateTransform : TransformState::FlattenTransform);
+        return;
+    }
+    
+    o->mapLocalToContainer(repaintContainer, fixed, useTransforms, transformState);
+}
+
+void RenderBox::mapAbsoluteToLocalPoint(bool fixed, bool useTransforms, TransformState& transformState) const
+{
+    // We don't expect absoluteToLocal() to be called during layout (yet)
+    ASSERT(!view() || !view()->layoutStateEnabled());
+    
+    bool isFixedPos = style()->position() == FixedPosition;
+    bool hasTransform = hasLayer() && layer()->transform();
+    if (hasTransform) {
+        // If this box has a transform, it acts as a fixed position container for fixed descendants,
+        // and may itself also be fixed position. So propagate 'fixed' up only if this box is fixed position.
+        fixed &= isFixedPos;
+    } else
+        fixed |= isFixedPos;
+    
+    RenderObject* o = container();
+    if (!o)
+        return;
+
+    o->mapAbsoluteToLocalPoint(fixed, useTransforms, transformState);
+
+    IntSize containerOffset = offsetFromContainer(o, IntPoint());
+
+    bool preserve3D = useTransforms && (o->style()->preserves3D() || style()->preserves3D());
+    if (useTransforms && shouldUseTransformFromContainer(o)) {
+        TransformationMatrix t;
+        getTransformFromContainer(o, containerOffset, t);
+        transformState.applyTransform(t, preserve3D ? TransformState::AccumulateTransform : TransformState::FlattenTransform);
+    } else
+        transformState.move(-containerOffset.width(), -containerOffset.height(), preserve3D ? TransformState::AccumulateTransform : TransformState::FlattenTransform);
+}
+
+IntSize RenderBox::offsetFromContainer(RenderObject* o, const IntPoint& point) const
+{
+    ASSERT(o == container());
+
+    IntSize offset;    
+    if (isRelPositioned())
+        offset += relativePositionOffset();
+
+    if (!isInline() || isReplaced()) {
+        if (style()->position() != AbsolutePosition && style()->position() != FixedPosition) {
+            o->adjustForColumns(offset, IntPoint(point.x() + x(), point.y() + y()));
+            offset += locationOffsetIncludingFlipping();
+        } else
+            offset += locationOffset();
+    }
+
+    if (o->hasOverflowClip())
+        offset -= toRenderBox(o)->layer()->scrolledContentOffset();
+
+    if (style()->position() == AbsolutePosition && o->isRelPositioned() && o->isRenderInline())
+        offset += toRenderInline(o)->relativePositionedInlineOffset(this);
+
+    return offset;
+}
+
+InlineBox* RenderBox::createInlineBox()
+{
+    return new (renderArena()) InlineBox(this);
+}
+
+void RenderBox::dirtyLineBoxes(bool fullLayout)
+{
+    if (m_inlineBoxWrapper) {
+        if (fullLayout) {
+            m_inlineBoxWrapper->destroy(renderArena());
+            m_inlineBoxWrapper = 0;
+        } else
+            m_inlineBoxWrapper->dirtyLineBoxes();
+    }
+}
+
+void RenderBox::positionLineBox(InlineBox* box)
+{
+    if (isPositioned()) {
+        // Cache the x position only if we were an INLINE type originally.
+        bool wasInline = style()->isOriginalDisplayInlineType();
+        if (wasInline && style()->hasStaticX()) {
+            // The value is cached in the xPos of the box.  We only need this value if
+            // our object was inline originally, since otherwise it would have ended up underneath
+            // the inlines.
+            layer()->setStaticX(box->x());
+            setChildNeedsLayout(true, false); // Just go ahead and mark the positioned object as needing layout, so it will update its position properly.
+        } else if (!wasInline && style()->hasStaticY()) {
+            // Our object was a block originally, so we make our normal flow position be
+            // just below the line box (as though all the inlines that came before us got
+            // wrapped in an anonymous block, which is what would have happened had we been
+            // in flow).  This value was cached in the y() of the box.
+            layer()->setStaticY(box->y());
+            setChildNeedsLayout(true, false); // Just go ahead and mark the positioned object as needing layout, so it will update its position properly.
+        }
+
+        // Nuke the box.
+        box->remove();
+        box->destroy(renderArena());
+    } else if (isReplaced()) {
+        setLocation(box->x(), box->y());
+        m_inlineBoxWrapper = box;
+    }
+}
+
+void RenderBox::deleteLineBoxWrapper()
+{
+    if (m_inlineBoxWrapper) {
+        if (!documentBeingDestroyed())
+            m_inlineBoxWrapper->remove();
+        m_inlineBoxWrapper->destroy(renderArena());
+        m_inlineBoxWrapper = 0;
+    }
+}
+
+IntRect RenderBox::clippedOverflowRectForRepaint(RenderBoxModelObject* repaintContainer)
+{
+    if (style()->visibility() != VISIBLE && !enclosingLayer()->hasVisibleContent())
+        return IntRect();
+
+    IntRect r = visualOverflowRect();
+
+    RenderView* v = view();
+    if (v) {
+        // FIXME: layoutDelta needs to be applied in parts before/after transforms and
+        // repaint containers. https://bugs.webkit.org/show_bug.cgi?id=23308
+        r.move(v->layoutDelta());
+    }
+    
+    if (style()) {
+        if (style()->hasAppearance())
+            // The theme may wish to inflate the rect used when repainting.
+            theme()->adjustRepaintRect(this, r);
+
+        // We have to use maximalOutlineSize() because a child might have an outline
+        // that projects outside of our overflowRect.
+        if (v) {
+            ASSERT(style()->outlineSize() <= v->maximalOutlineSize());
+            r.inflate(v->maximalOutlineSize());
+        }
+    }
+    
+    computeRectForRepaint(repaintContainer, r);
+    return r;
+}
+
+void RenderBox::computeRectForRepaint(RenderBoxModelObject* repaintContainer, IntRect& rect, bool fixed)
+{
+    // The rect we compute at each step is shifted by our x/y offset in the parent container's coordinate space.
+    // Only when we cross a writing mode boundary will we have to possibly flipForWritingMode (to convert into a more appropriate
+    // offset corner for the enclosing container).  This allows for a fully RL or BT document to repaint
+    // properly even during layout, since the rect remains flipped all the way until the end.
+    //
+    // RenderView::computeRectForRepaint then converts the rect to physical coordinates.  We also convert to
+    // physical when we hit a repaintContainer boundary.  Therefore the final rect returned is always in the
+    // physical coordinate space of the repaintContainer.
+    if (RenderView* v = view()) {
+        // LayoutState is only valid for root-relative repainting
+        if (v->layoutStateEnabled() && !repaintContainer) {
+            LayoutState* layoutState = v->layoutState();
+
+            if (layer() && layer()->transform())
+                rect = layer()->transform()->mapRect(rect);
+
+            if (style()->position() == RelativePosition && layer())
+                rect.move(layer()->relativePositionOffset());
+
+            rect.move(x(), y());
+            rect.move(layoutState->m_paintOffset);
+            if (layoutState->m_clipped)
+                rect.intersect(layoutState->m_clipRect);
+            return;
+        }
+    }
+
+    if (hasReflection())
+        rect.unite(reflectedRect(rect));
+
+    if (repaintContainer == this) {
+        if (repaintContainer->style()->isFlippedBlocksWritingMode())
+            flipForWritingMode(rect);
+        return;
+    }
+
+    bool containerSkipped;
+    RenderObject* o = container(repaintContainer, &containerSkipped);
+    if (!o)
+        return;
+
+    if (isWritingModeRoot() && !isPositioned())
+        flipForWritingMode(rect);
+    IntPoint topLeft = rect.location();
+    topLeft.move(x(), y());
+
+    EPosition position = style()->position();
+
+    // We are now in our parent container's coordinate space.  Apply our transform to obtain a bounding box
+    // in the parent's coordinate space that encloses us.
+    if (layer() && layer()->transform()) {
+        fixed = position == FixedPosition;
+        rect = layer()->transform()->mapRect(rect);
+        topLeft = rect.location();
+        topLeft.move(x(), y());
+    } else if (position == FixedPosition)
+        fixed = true;
+
+    if (position == AbsolutePosition && o->isRelPositioned() && o->isRenderInline())
+        topLeft += toRenderInline(o)->relativePositionedInlineOffset(this);
+    else if (position == RelativePosition && layer()) {
+        // Apply the relative position offset when invalidating a rectangle.  The layer
+        // is translated, but the render box isn't, so we need to do this to get the
+        // right dirty rect.  Since this is called from RenderObject::setStyle, the relative position
+        // flag on the RenderObject has been cleared, so use the one on the style().
+        topLeft += layer()->relativePositionOffset();
+    }
+    
+    if (o->isBlockFlow() && position != AbsolutePosition && position != FixedPosition) {
+        RenderBlock* cb = toRenderBlock(o);
+        if (cb->hasColumns()) {
+            IntRect repaintRect(topLeft, rect.size());
+            cb->adjustRectForColumns(repaintRect);
+            topLeft = repaintRect.location();
+            rect = repaintRect;
+        }
+    }
+
+    // FIXME: We ignore the lightweight clipping rect that controls use, since if |o| is in mid-layout,
+    // its controlClipRect will be wrong. For overflow clip we use the values cached by the layer.
+    if (o->hasOverflowClip()) {
+        RenderBox* containerBox = toRenderBox(o);
+
+        // o->height() is inaccurate if we're in the middle of a layout of |o|, so use the
+        // layer's size instead.  Even if the layer's size is wrong, the layer itself will repaint
+        // anyway if its size does change.
+        topLeft -= containerBox->layer()->scrolledContentOffset(); // For overflow:auto/scroll/hidden.
+
+        IntRect repaintRect(topLeft, rect.size());
+        IntRect boxRect(0, 0, containerBox->layer()->width(), containerBox->layer()->height());
+        rect = intersection(repaintRect, boxRect);
+        if (rect.isEmpty())
+            return;
+    } else
+        rect.setLocation(topLeft);
+
+    if (containerSkipped) {
+        // If the repaintContainer is below o, then we need to map the rect into repaintContainer's coordinates.
+        IntSize containerOffset = repaintContainer->offsetFromAncestorContainer(o);
+        rect.move(-containerOffset);
+        return;
+    }
+
+    o->computeRectForRepaint(repaintContainer, rect, fixed);
+}
+
+void RenderBox::repaintDuringLayoutIfMoved(const IntRect& rect)
+{
+    int newX = x();
+    int newY = y();
+    int newWidth = width();
+    int newHeight = height();
+    if (rect.x() != newX || rect.y() != newY) {
+        // The child moved.  Invalidate the object's old and new positions.  We have to do this
+        // since the object may not have gotten a layout.
+        m_frameRect = rect;
+        repaint();
+        repaintOverhangingFloats(true);
+        m_frameRect = IntRect(newX, newY, newWidth, newHeight);
+        repaint();
+        repaintOverhangingFloats(true);
+    }
+}
+
+#ifdef ANDROID_LAYOUT
+void RenderBox::setVisibleWidth(int newWidth) {
+    const Settings* settings = document()->settings();
+    ASSERT(settings);
+    if (settings->layoutAlgorithm() != Settings::kLayoutFitColumnToScreen
+        || m_visibleWidth == newWidth)
+        return;
+    m_isVisibleWidthChangedBeforeLayout = true;
+    m_visibleWidth = newWidth;
+}
+
+bool RenderBox::checkAndSetRelayoutChildren(bool* relayoutChildren) {
+    if (m_isVisibleWidthChangedBeforeLayout) {
+        m_isVisibleWidthChangedBeforeLayout = false;
+        *relayoutChildren = true;
+        return true;
+    }
+    return false;
+}
+#endif
+
+void RenderBox::computeLogicalWidth()
+{
+#ifdef ANDROID_LAYOUT
+    if (view()->frameView())
+        setVisibleWidth(view()->frameView()->textWrapWidth());
+#endif
+
+    if (isPositioned()) {
+        // FIXME: This calculation is not patched for block-flow yet.
+        // https://bugs.webkit.org/show_bug.cgi?id=46500
+        computePositionedLogicalWidth();
+        return;
+    }
+
+    // If layout is limited to a subtree, the subtree root's logical width does not change.
+    if (node() && view()->frameView() && view()->frameView()->layoutRoot(true) == this)
+        return;
+
+    // The parent box is flexing us, so it has increased or decreased our
+    // width.  Use the width from the style context.
+    // FIXME: Account for block-flow in flexible boxes.
+    // https://bugs.webkit.org/show_bug.cgi?id=46418
+    if (hasOverrideSize() &&  parent()->style()->boxOrient() == HORIZONTAL
+            && parent()->isFlexibleBox() && parent()->isFlexingChildren()) {
+        setLogicalWidth(overrideSize());
+        return;
+    }
+
+    // FIXME: Account for block-flow in flexible boxes.
+    // https://bugs.webkit.org/show_bug.cgi?id=46418
+    bool inVerticalBox = parent()->isFlexibleBox() && (parent()->style()->boxOrient() == VERTICAL);
+    bool stretching = (parent()->style()->boxAlign() == BSTRETCH);
+    bool treatAsReplaced = shouldComputeSizeAsReplaced() && (!inVerticalBox || !stretching);
+
+    Length logicalWidthLength = (treatAsReplaced) ? Length(computeReplacedLogicalWidth(), Fixed) : style()->logicalWidth();
+
+    RenderBlock* cb = containingBlock();
+    int containerLogicalWidth = max(0, containingBlockLogicalWidthForContent());
+    bool hasPerpendicularContainingBlock = cb->style()->isHorizontalWritingMode() != style()->isHorizontalWritingMode();
+    int containerWidthInInlineDirection = containerLogicalWidth;
+    if (hasPerpendicularContainingBlock)
+        containerWidthInInlineDirection = perpendicularContainingBlockLogicalHeight();
+    
+    if (isInline() && !isInlineBlockOrInlineTable()) {
+        // just calculate margins
+        setMarginStart(style()->marginStart().calcMinValue(containerLogicalWidth));
+        setMarginEnd(style()->marginEnd().calcMinValue(containerLogicalWidth));
+#ifdef ANDROID_LAYOUT
+        if (treatAsReplaced) {
+#else
+        if (treatAsReplaced)
+#endif
+            setLogicalWidth(max(logicalWidthLength.value() + borderAndPaddingLogicalWidth(), minPreferredLogicalWidth()));
+
+#ifdef ANDROID_LAYOUT
+            // in SSR mode with replaced box, if the box width is wider than the container width,
+            // it will be shrinked to fit to the container.
+            if (containerLogicalWidth && (width() + m_marginLeft + m_marginRight) > containerLogicalWidth &&
+                    document()->frame()->settings()->layoutAlgorithm() == Settings::kLayoutSSR) {
+                m_marginLeft = m_marginRight = 0;
+                setWidth(containerLogicalWidth);
+                m_minPreferredLogicalWidth = m_maxPreferredLogicalWidth = containerLogicalWidth;
+            }
+        }
+#endif
+        return;
+    }
+
+    // Width calculations
+    if (treatAsReplaced)
+        setLogicalWidth(logicalWidthLength.value() + borderAndPaddingLogicalWidth());
+    else {
+        // Calculate LogicalWidth
+        setLogicalWidth(computeLogicalWidthUsing(LogicalWidth, containerWidthInInlineDirection));
+
+        // Calculate MaxLogicalWidth
+        if (!style()->logicalMaxWidth().isUndefined()) {
+            int maxLogicalWidth = computeLogicalWidthUsing(MaxLogicalWidth, containerWidthInInlineDirection);
+            if (logicalWidth() > maxLogicalWidth) {
+                setLogicalWidth(maxLogicalWidth);
+                logicalWidthLength = style()->logicalMaxWidth();
+            }
+        }
+
+        // Calculate MinLogicalWidth
+        int minLogicalWidth = computeLogicalWidthUsing(MinLogicalWidth, containerWidthInInlineDirection);
+        if (logicalWidth() < minLogicalWidth) {
+            setLogicalWidth(minLogicalWidth);
+            logicalWidthLength = style()->logicalMinWidth();
+        }
+    }
+
+    // Fieldsets are currently the only objects that stretch to their minimum width.
+    if (stretchesToMinIntrinsicLogicalWidth()) {
+        setLogicalWidth(max(logicalWidth(), minPreferredLogicalWidth()));
+        logicalWidthLength = Length(logicalWidth(), Fixed);
+    }
+
+    // Margin calculations.
+    if (logicalWidthLength.isAuto() || hasPerpendicularContainingBlock || isFloating() || isInline()) {
+        setMarginStart(style()->marginStart().calcMinValue(containerLogicalWidth));
+        setMarginEnd(style()->marginEnd().calcMinValue(containerLogicalWidth));
+    } else
+        computeInlineDirectionMargins(cb, containerLogicalWidth, logicalWidth());
+
+#ifdef ANDROID_LAYOUT
+    // in SSR mode with non-replaced box, we use ANDROID_SSR_MARGIN_PADDING for left/right margin.
+    // If the box width is wider than the container width, it will be shrinked to fit to the container.
+    if (containerLogicalWidth && !treatAsReplaced &&
+            document()->settings()->layoutAlgorithm() == Settings::kLayoutSSR) {
+        setWidth(width() + m_marginLeft + m_marginRight);
+        m_marginLeft = m_marginLeft > ANDROID_SSR_MARGIN_PADDING ? ANDROID_SSR_MARGIN_PADDING : m_marginLeft;
+        m_marginRight = m_marginRight > ANDROID_SSR_MARGIN_PADDING ? ANDROID_SSR_MARGIN_PADDING : m_marginRight;
+        if (width() > containerLogicalWidth) {
+            m_minPreferredLogicalWidth = m_maxPreferredLogicalWidth = containerLogicalWidth-(m_marginLeft + m_marginRight);
+            setWidth(m_minPreferredLogicalWidth);
+        } else
+            setWidth(width() -(m_marginLeft + m_marginRight));
+    }
+#endif
+
+    if (!hasPerpendicularContainingBlock && containerLogicalWidth && containerLogicalWidth != (logicalWidth() + marginStart() + marginEnd())
+            && !isFloating() && !isInline() && !cb->isFlexibleBox())
+        cb->setMarginEndForChild(this, containerLogicalWidth - logicalWidth() - cb->marginStartForChild(this));
+}
+
+int RenderBox::computeLogicalWidthUsing(LogicalWidthType widthType, int availableLogicalWidth)
+{
+    int logicalWidthResult = logicalWidth();
+    Length logicalWidth;
+    if (widthType == LogicalWidth)
+        logicalWidth = style()->logicalWidth();
+    else if (widthType == MinLogicalWidth)
+        logicalWidth = style()->logicalMinWidth();
+    else
+        logicalWidth = style()->logicalMaxWidth();
+
+    if (logicalWidth.isIntrinsicOrAuto()) {
+        int marginStart = style()->marginStart().calcMinValue(availableLogicalWidth);
+        int marginEnd = style()->marginEnd().calcMinValue(availableLogicalWidth);
+        if (availableLogicalWidth)
+            logicalWidthResult = availableLogicalWidth - marginStart - marginEnd;
+
+        if (sizesToIntrinsicLogicalWidth(widthType)) {
+            logicalWidthResult = max(logicalWidthResult, minPreferredLogicalWidth());
+            logicalWidthResult = min(logicalWidthResult, maxPreferredLogicalWidth());
+        }
+    } else // FIXME: If the containing block flow is perpendicular to our direction we need to use the available logical height instead.
+        logicalWidthResult = computeBorderBoxLogicalWidth(logicalWidth.calcValue(availableLogicalWidth)); 
+
+    return logicalWidthResult;
+}
+
+bool RenderBox::sizesToIntrinsicLogicalWidth(LogicalWidthType widthType) const
+{
+    // Marquees in WinIE are like a mixture of blocks and inline-blocks.  They size as though they're blocks,
+    // but they allow text to sit on the same line as the marquee.
+    if (isFloating() || (isInlineBlockOrInlineTable() && !isHTMLMarquee()))
+        return true;
+
+    // This code may look a bit strange.  Basically width:intrinsic should clamp the size when testing both
+    // min-width and width.  max-width is only clamped if it is also intrinsic.
+    Length logicalWidth = (widthType == MaxLogicalWidth) ? style()->logicalMaxWidth() : style()->logicalWidth();
+    if (logicalWidth.type() == Intrinsic)
+        return true;
+
+    // Children of a horizontal marquee do not fill the container by default.
+    // FIXME: Need to deal with MAUTO value properly.  It could be vertical.
+    // FIXME: Think about block-flow here.  Need to find out how marquee direction relates to
+    // block-flow (as well as how marquee overflow should relate to block flow).
+    // https://bugs.webkit.org/show_bug.cgi?id=46472
+    if (parent()->style()->overflowX() == OMARQUEE) {
+        EMarqueeDirection dir = parent()->style()->marqueeDirection();
+        if (dir == MAUTO || dir == MFORWARD || dir == MBACKWARD || dir == MLEFT || dir == MRIGHT)
+            return true;
+    }
+
+    // Flexible horizontal boxes lay out children at their intrinsic widths.  Also vertical boxes
+    // that don't stretch their kids lay out their children at their intrinsic widths.
+    // FIXME: Think about block-flow here.
+    // https://bugs.webkit.org/show_bug.cgi?id=46473
+    if (parent()->isFlexibleBox()
+            && (parent()->style()->boxOrient() == HORIZONTAL || parent()->style()->boxAlign() != BSTRETCH))
+        return true;
+
+    // Button, input, select, textarea, legend and datagrid treat
+    // width value of 'auto' as 'intrinsic' unless it's in a
+    // stretching vertical flexbox.
+    // FIXME: Think about block-flow here.
+    // https://bugs.webkit.org/show_bug.cgi?id=46473
+    if (logicalWidth.type() == Auto && !(parent()->isFlexibleBox() && parent()->style()->boxOrient() == VERTICAL && parent()->style()->boxAlign() == BSTRETCH) && node() && (node()->hasTagName(inputTag) || node()->hasTagName(selectTag) || node()->hasTagName(buttonTag) || node()->hasTagName(textareaTag) || node()->hasTagName(legendTag) || node()->hasTagName(datagridTag)))
+        return true;
+
+    return false;
+}
+
+void RenderBox::computeInlineDirectionMargins(RenderBlock* containingBlock, int containerWidth, int childWidth)
+{
+    const RenderStyle* containingBlockStyle = containingBlock->style();
+    Length marginStartLength = style()->marginStartUsing(containingBlockStyle);
+    Length marginEndLength = style()->marginEndUsing(containingBlockStyle);
+    
+    // Case One: The object is being centered in the containing block's available logical width.
+    if ((marginStartLength.isAuto() && marginEndLength.isAuto() && childWidth < containerWidth)
+        || (!marginStartLength.isAuto() && !marginEndLength.isAuto() && containingBlock->style()->textAlign() == WEBKIT_CENTER)) {
+        containingBlock->setMarginStartForChild(this, max(0, (containerWidth - childWidth) / 2));
+        containingBlock->setMarginEndForChild(this, containerWidth - childWidth - containingBlock->marginStartForChild(this));
+        return;
+    } 
+    
+    // Case Two: The object is being pushed to the start of the containing block's available logical width.
+    if (marginEndLength.isAuto() && childWidth < containerWidth) {
+        containingBlock->setMarginStartForChild(this, marginStartLength.calcValue(containerWidth));
+        containingBlock->setMarginEndForChild(this, containerWidth - childWidth - containingBlock->marginStartForChild(this));
+        return;
+    } 
+    
+    // Case Three: The object is being pushed to the end of the containing block's available logical width.
+    bool pushToEndFromTextAlign = !marginEndLength.isAuto() && ((!containingBlockStyle->isLeftToRightDirection() && containingBlockStyle->textAlign() == WEBKIT_LEFT)
+        || (containingBlockStyle->isLeftToRightDirection() && containingBlockStyle->textAlign() == WEBKIT_RIGHT));
+    if ((marginStartLength.isAuto() && childWidth < containerWidth) || pushToEndFromTextAlign) {
+        containingBlock->setMarginEndForChild(this, marginEndLength.calcValue(containerWidth));
+        containingBlock->setMarginStartForChild(this, containerWidth - childWidth - containingBlock->marginEndForChild(this));
+        return;
+    } 
+    
+    // Case Four: Either no auto margins, or our width is >= the container width (css2.1, 10.3.3).  In that case
+    // auto margins will just turn into 0.
+    containingBlock->setMarginStartForChild(this, marginStartLength.calcMinValue(containerWidth));
+    containingBlock->setMarginEndForChild(this, marginEndLength.calcMinValue(containerWidth));
+}
+
+void RenderBox::computeLogicalHeight()
+{
+    // Cell height is managed by the table and inline non-replaced elements do not support a height property.
+    if (isTableCell() || (isInline() && !isReplaced()))
+        return;
+
+    Length h;
+    if (isPositioned()) {
+        // FIXME: This calculation is not patched for block-flow yet.
+        // https://bugs.webkit.org/show_bug.cgi?id=46500
+        computePositionedLogicalHeight();
+    } else {
+        RenderBlock* cb = containingBlock();
+        bool hasPerpendicularContainingBlock = cb->style()->isHorizontalWritingMode() != style()->isHorizontalWritingMode();
+    
+        if (!hasPerpendicularContainingBlock)
+            computeBlockDirectionMargins(cb);
+
+        // For tables, calculate margins only.
+        if (isTable()) {
+            if (hasPerpendicularContainingBlock)
+                computeInlineDirectionMargins(cb, containingBlockLogicalWidthForContent(), logicalHeight());
+            return;
+        }
+
+        // FIXME: Account for block-flow in flexible boxes.
+        // https://bugs.webkit.org/show_bug.cgi?id=46418
+        bool inHorizontalBox = parent()->isFlexibleBox() && parent()->style()->boxOrient() == HORIZONTAL;
+        bool stretching = parent()->style()->boxAlign() == BSTRETCH;
+        bool treatAsReplaced = shouldComputeSizeAsReplaced() && (!inHorizontalBox || !stretching);
+        bool checkMinMaxHeight = false;
+
+        // The parent box is flexing us, so it has increased or decreased our height.  We have to
+        // grab our cached flexible height.
+        // FIXME: Account for block-flow in flexible boxes.
+        // https://bugs.webkit.org/show_bug.cgi?id=46418
+        if (hasOverrideSize() && parent()->isFlexibleBox() && parent()->style()->boxOrient() == VERTICAL
+                && parent()->isFlexingChildren())
+            h = Length(overrideSize() - borderAndPaddingLogicalHeight(), Fixed);
+        else if (treatAsReplaced)
+            h = Length(computeReplacedLogicalHeight(), Fixed);
+        else {
+            h = style()->logicalHeight();
+            checkMinMaxHeight = true;
+        }
+
+        // Block children of horizontal flexible boxes fill the height of the box.
+        // FIXME: Account for block-flow in flexible boxes.
+        // https://bugs.webkit.org/show_bug.cgi?id=46418
+        if (h.isAuto() && parent()->isFlexibleBox() && parent()->style()->boxOrient() == HORIZONTAL
+                && parent()->isStretchingChildren()) {
+            h = Length(parentBox()->contentLogicalHeight() - marginBefore() - marginAfter() - borderAndPaddingLogicalHeight(), Fixed);
+            checkMinMaxHeight = false;
+        }
+
+        int heightResult;
+        if (checkMinMaxHeight) {
+#ifdef ANDROID_LAYOUT
+            // in SSR mode, ignore CSS height as layout is so different
+            if (document()->settings()->layoutAlgorithm() == Settings::kLayoutSSR)
+                heightResult = -1;
+            else
+#endif
+            heightResult = computeLogicalHeightUsing(style()->logicalHeight());
+            if (heightResult == -1)
+                heightResult = logicalHeight();
+            int minH = computeLogicalHeightUsing(style()->logicalMinHeight()); // Leave as -1 if unset.
+            int maxH = style()->logicalMaxHeight().isUndefined() ? heightResult : computeLogicalHeightUsing(style()->logicalMaxHeight());
+            if (maxH == -1)
+                maxH = heightResult;
+            heightResult = min(maxH, heightResult);
+            heightResult = max(minH, heightResult);
+        } else {
+            // The only times we don't check min/max height are when a fixed length has
+            // been given as an override.  Just use that.  The value has already been adjusted
+            // for box-sizing.
+            heightResult = h.value() + borderAndPaddingLogicalHeight();
+        }
+
+        setLogicalHeight(heightResult);
+        
+        if (hasPerpendicularContainingBlock)
+            computeInlineDirectionMargins(cb, containingBlockLogicalWidthForContent(), heightResult);
+    }
+
+    // WinIE quirk: The <html> block always fills the entire canvas in quirks mode.  The <body> always fills the
+    // <html> block in quirks mode.  Only apply this quirk if the block is normal flow and no height
+    // is specified. When we're printing, we also need this quirk if the body or root has a percentage 
+    // height since we don't set a height in RenderView when we're printing. So without this quirk, the 
+    // height has nothing to be a percentage of, and it ends up being 0. That is bad.
+    bool paginatedContentNeedsBaseHeight = document()->printing() && h.isPercent()
+        && (isRoot() || (isBody() && document()->documentElement()->renderer()->style()->logicalHeight().isPercent()));
+    if (stretchesToViewport() || paginatedContentNeedsBaseHeight) {
+        // FIXME: Finish accounting for block flow here.
+        // https://bugs.webkit.org/show_bug.cgi?id=46603
+        int margins = collapsedMarginBefore() + collapsedMarginAfter();
+        int visHeight;
+        if (document()->printing())
+            visHeight = static_cast<int>(view()->pageLogicalHeight());
+        else  {
+            if (style()->isHorizontalWritingMode())
+                visHeight = view()->viewHeight();
+            else
+                visHeight = view()->viewWidth();
+        }
+        if (isRoot())
+            setLogicalHeight(max(logicalHeight(), visHeight - margins));
+        else {
+            int marginsBordersPadding = margins + parentBox()->marginBefore() + parentBox()->marginAfter() + parentBox()->borderAndPaddingLogicalHeight();
+            setLogicalHeight(max(logicalHeight(), visHeight - marginsBordersPadding));
+        }
+    }
+}
+
+int RenderBox::computeLogicalHeightUsing(const Length& h)
+{
+    int logicalHeight = -1;
+    if (!h.isAuto()) {
+        if (h.isFixed())
+            logicalHeight = h.value();
+        else if (h.isPercent())
+            logicalHeight = computePercentageLogicalHeight(h);
+        if (logicalHeight != -1) {
+            logicalHeight = computeBorderBoxLogicalHeight(logicalHeight);
+            return logicalHeight;
+        }
+    }
+    return logicalHeight;
+}
+
+int RenderBox::computePercentageLogicalHeight(const Length& height)
+{
+    int result = -1;
+    bool skippedAutoHeightContainingBlock = false;
+    RenderBlock* cb = containingBlock();
+    if (document()->inQuirksMode()) {
+        // In quirks mode, blocks with auto height are skipped, and we keep looking for an enclosing
+        // block that may have a specified height and then use it.  In strict mode, this violates the
+        // specification, which states that percentage heights just revert to auto if the containing
+        // block has an auto height.
+        while (!cb->isRenderView() && !cb->isBody() && !cb->isTableCell() && !cb->isPositioned() && cb->style()->logicalHeight().isAuto()) {
+            skippedAutoHeightContainingBlock = true;
+            cb = cb->containingBlock();
+            cb->addPercentHeightDescendant(this);
+        }
+    }
+
+    // A positioned element that specified both top/bottom or that specifies height should be treated as though it has a height
+    // explicitly specified that can be used for any percentage computations.
+    // FIXME: We can't just check top/bottom here.
+    // https://bugs.webkit.org/show_bug.cgi?id=46500
+    bool isPositionedWithSpecifiedHeight = cb->isPositioned() && (!cb->style()->logicalHeight().isAuto() || (!cb->style()->top().isAuto() && !cb->style()->bottom().isAuto()));
+
+    bool includeBorderPadding = isTable();
+
+    // Table cells violate what the CSS spec says to do with heights.  Basically we
+    // don't care if the cell specified a height or not.  We just always make ourselves
+    // be a percentage of the cell's current content height.
+    if (cb->isTableCell()) {
+        if (!skippedAutoHeightContainingBlock) {
+            result = cb->overrideSize();
+            if (result == -1) {
+                // Normally we would let the cell size intrinsically, but scrolling overflow has to be
+                // treated differently, since WinIE lets scrolled overflow regions shrink as needed.
+                // While we can't get all cases right, we can at least detect when the cell has a specified
+                // height or when the table has a specified height.  In these cases we want to initially have
+                // no size and allow the flexing of the table or the cell to its specified height to cause us
+                // to grow to fill the space.  This could end up being wrong in some cases, but it is
+                // preferable to the alternative (sizing intrinsically and making the row end up too big).
+                RenderTableCell* cell = toRenderTableCell(cb);
+                if (scrollsOverflowY() && (!cell->style()->logicalHeight().isAuto() || !cell->table()->style()->logicalHeight().isAuto()))
+                    return 0;
+                return -1;
+            }
+            includeBorderPadding = true;
+        }
+    }
+    // Otherwise we only use our percentage height if our containing block had a specified
+    // height.
+    else if (cb->style()->logicalHeight().isFixed())
+        result = cb->computeContentBoxLogicalHeight(cb->style()->logicalHeight().value());
+    else if (cb->style()->logicalHeight().isPercent() && !isPositionedWithSpecifiedHeight) {
+        // We need to recur and compute the percentage height for our containing block.
+        result = cb->computePercentageLogicalHeight(cb->style()->logicalHeight());
+        if (result != -1)
+            result = cb->computeContentBoxLogicalHeight(result);
+    } else if (cb->isRenderView() || (cb->isBody() && document()->inQuirksMode()) || isPositionedWithSpecifiedHeight) {
+        // Don't allow this to affect the block' height() member variable, since this
+        // can get called while the block is still laying out its kids.
+        int oldHeight = cb->logicalHeight();
+        cb->computeLogicalHeight();
+        result = cb->contentLogicalHeight();
+        cb->setLogicalHeight(oldHeight);
+    } else if (cb->isRoot() && isPositioned())
+        // Match the positioned objects behavior, which is that positioned objects will fill their viewport
+        // always.  Note we could only hit this case by recurring into computePercentageLogicalHeight on a positioned containing block.
+        result = cb->computeContentBoxLogicalHeight(cb->availableLogicalHeight());
+
+    if (result != -1) {
+        result = height.calcValue(result);
+        if (includeBorderPadding) {
+            // It is necessary to use the border-box to match WinIE's broken
+            // box model.  This is essential for sizing inside
+            // table cells using percentage heights.
+            result -= borderAndPaddingLogicalHeight();
+            result = max(0, result);
+        }
+    }
+    return result;
+}
+
+int RenderBox::computeReplacedLogicalWidth(bool includeMaxWidth) const
+{
+    int logicalWidth = computeReplacedLogicalWidthUsing(style()->logicalWidth());
+    int minLogicalWidth = computeReplacedLogicalWidthUsing(style()->logicalMinWidth());
+    int maxLogicalWidth = !includeMaxWidth || style()->logicalMaxWidth().isUndefined() ? logicalWidth : computeReplacedLogicalWidthUsing(style()->logicalMaxWidth());
+
+    return max(minLogicalWidth, min(logicalWidth, maxLogicalWidth));
+}
+
+int RenderBox::computeReplacedLogicalWidthUsing(Length logicalWidth) const
+{
+    switch (logicalWidth.type()) {
+        case Fixed:
+            return computeContentBoxLogicalWidth(logicalWidth.value());
+        case Percent: {
+            // FIXME: containingBlockLogicalWidthForContent() is wrong if the replaced element's block-flow is perpendicular to the
+            // containing block's block-flow.
+            // https://bugs.webkit.org/show_bug.cgi?id=46496
+            const int cw = isPositioned() ? containingBlockWidthForPositioned(toRenderBoxModelObject(container())) : containingBlockLogicalWidthForContent();
+            if (cw > 0)
+                return computeContentBoxLogicalWidth(logicalWidth.calcMinValue(cw));
+        }
+        // fall through
+        default:
+            return intrinsicLogicalWidth();
+     }
+}
+
+int RenderBox::computeReplacedLogicalHeight() const
+{
+    int logicalHeight = computeReplacedLogicalHeightUsing(style()->logicalHeight());
+    int minLogicalHeight = computeReplacedLogicalHeightUsing(style()->logicalMinHeight());
+    int maxLogicalHeight = style()->logicalMaxHeight().isUndefined() ? logicalHeight : computeReplacedLogicalHeightUsing(style()->logicalMaxHeight());
+
+    return max(minLogicalHeight, min(logicalHeight, maxLogicalHeight));
+}
+
+int RenderBox::computeReplacedLogicalHeightUsing(Length logicalHeight) const
+{
+    switch (logicalHeight.type()) {
+        case Fixed:
+            return computeContentBoxLogicalHeight(logicalHeight.value());
+        case Percent:
+        {
+            RenderObject* cb = isPositioned() ? container() : containingBlock();
+            while (cb->isAnonymous()) {
+                cb = cb->containingBlock();
+                toRenderBlock(cb)->addPercentHeightDescendant(const_cast<RenderBox*>(this));
+            }
+
+            // FIXME: This calculation is not patched for block-flow yet.
+            // https://bugs.webkit.org/show_bug.cgi?id=46500
+            if (cb->isPositioned() && cb->style()->height().isAuto() && !(cb->style()->top().isAuto() || cb->style()->bottom().isAuto())) {
+                ASSERT(cb->isRenderBlock());
+                RenderBlock* block = toRenderBlock(cb);
+                int oldHeight = block->height();
+                block->computeLogicalHeight();
+                int newHeight = block->computeContentBoxLogicalHeight(block->contentHeight());
+                block->setHeight(oldHeight);
+                return computeContentBoxLogicalHeight(logicalHeight.calcValue(newHeight));
+            }
+            
+            // FIXME: availableLogicalHeight() is wrong if the replaced element's block-flow is perpendicular to the
+            // containing block's block-flow.
+            // https://bugs.webkit.org/show_bug.cgi?id=46496
+            int availableHeight = isPositioned() ? containingBlockHeightForPositioned(toRenderBoxModelObject(cb)) : toRenderBox(cb)->availableLogicalHeight();
+
+            // It is necessary to use the border-box to match WinIE's broken
+            // box model.  This is essential for sizing inside
+            // table cells using percentage heights.
+            // FIXME: This needs to be made block-flow-aware.  If the cell and image are perpendicular block-flows, this isn't right.
+            // https://bugs.webkit.org/show_bug.cgi?id=46997
+            if (cb->isTableCell() && (cb->style()->logicalHeight().isAuto() || cb->style()->logicalHeight().isPercent())) {
+                // Don't let table cells squeeze percent-height replaced elements
+                // <http://bugs.webkit.org/show_bug.cgi?id=15359>
+                availableHeight = max(availableHeight, intrinsicLogicalHeight());
+                return logicalHeight.calcValue(availableHeight - borderAndPaddingLogicalHeight());
+            }
+
+            return computeContentBoxLogicalHeight(logicalHeight.calcValue(availableHeight));
+        }
+        default:
+            return intrinsicLogicalHeight();
+    }
+}
+
+int RenderBox::availableLogicalHeight() const
+{
+    return availableLogicalHeightUsing(style()->logicalHeight());
+}
+
+int RenderBox::availableLogicalHeightUsing(const Length& h) const
+{
+    if (h.isFixed())
+        return computeContentBoxLogicalHeight(h.value());
+
+    if (isRenderView())
+        return style()->isHorizontalWritingMode() ? toRenderView(this)->frameView()->visibleHeight() : toRenderView(this)->frameView()->visibleWidth();
+
+    // We need to stop here, since we don't want to increase the height of the table
+    // artificially.  We're going to rely on this cell getting expanded to some new
+    // height, and then when we lay out again we'll use the calculation below.
+    if (isTableCell() && (h.isAuto() || h.isPercent()))
+        return overrideSize() - borderAndPaddingLogicalWidth();
+
+    if (h.isPercent())
+       return computeContentBoxLogicalHeight(h.calcValue(containingBlock()->availableLogicalHeight()));
+
+    // FIXME: We can't just check top/bottom here.
+    // https://bugs.webkit.org/show_bug.cgi?id=46500
+    if (isRenderBlock() && isPositioned() && style()->height().isAuto() && !(style()->top().isAuto() || style()->bottom().isAuto())) {
+        RenderBlock* block = const_cast<RenderBlock*>(toRenderBlock(this));
+        int oldHeight = block->logicalHeight();
+        block->computeLogicalHeight();
+        int newHeight = block->computeContentBoxLogicalHeight(block->contentLogicalHeight());
+        block->setLogicalHeight(oldHeight);
+        return computeContentBoxLogicalHeight(newHeight);
+    }
+
+    return containingBlock()->availableLogicalHeight();
+}
+
+void RenderBox::computeBlockDirectionMargins(RenderBlock* containingBlock)
+{
+    if (isTableCell()) {
+        // FIXME: Not right if we allow cells to have different directionality than the table.  If we do allow this, though,
+        // we may just do it with an extra anonymous block inside the cell.
+        setMarginBefore(0);
+        setMarginAfter(0);
+        return;
+    }
+
+    // Margins are calculated with respect to the logical width of
+    // the containing block (8.3)
+    int cw = containingBlockLogicalWidthForContent();
+
+    RenderStyle* containingBlockStyle = containingBlock->style();
+    containingBlock->setMarginBeforeForChild(this, style()->marginBeforeUsing(containingBlockStyle).calcMinValue(cw));
+    containingBlock->setMarginAfterForChild(this, style()->marginAfterUsing(containingBlockStyle).calcMinValue(cw));
+}
+
+int RenderBox::containingBlockWidthForPositioned(const RenderBoxModelObject* containingBlock) const
+{
+#if PLATFORM(ANDROID)
+    // Fixed element's position should be decided by the visible screen size.
+    // That is in the doc coordindate.
+    if (style()->position() == FixedPosition && containingBlock->isRenderView()) {
+        const RenderView* view = toRenderView(containingBlock);
+        return PlatformBridge::screenWidthInDocCoord(view->frameView());
+    }
+#endif
+    if (containingBlock->isBox()) {
+        const RenderBox* containingBlockBox = toRenderBox(containingBlock);
+        return containingBlockBox->width() - containingBlockBox->borderLeft() - containingBlockBox->borderRight() - containingBlockBox->verticalScrollbarWidth();
+    }
+    
+    ASSERT(containingBlock->isRenderInline() && containingBlock->isRelPositioned());
+
+    const RenderInline* flow = toRenderInline(containingBlock);
+    InlineFlowBox* first = flow->firstLineBox();
+    InlineFlowBox* last = flow->lastLineBox();
+
+    // If the containing block is empty, return a width of 0.
+    if (!first || !last)
+        return 0;
+
+    int fromLeft;
+    int fromRight;
+    if (containingBlock->style()->isLeftToRightDirection()) {
+        fromLeft = first->logicalLeft() + first->borderLogicalLeft();
+        fromRight = last->logicalLeft() + last->logicalWidth() - last->borderLogicalRight();
+    } else {
+        fromRight = first->logicalLeft() + first->logicalWidth() - first->borderLogicalRight();
+        fromLeft = last->logicalLeft() + last->borderLogicalLeft();
+    }
+
+    return max(0, (fromRight - fromLeft));
+}
+
+int RenderBox::containingBlockHeightForPositioned(const RenderBoxModelObject* containingBlock) const
+{
+#if PLATFORM(ANDROID)
+    // Fixed element's position should be decided by the visible screen size.
+    // That is in the doc coordindate.
+    if (style()->position() == FixedPosition && containingBlock->isRenderView()) {
+        const RenderView* view = toRenderView(containingBlock);
+        return PlatformBridge::screenHeightInDocCoord(view->frameView());
+    }
+#endif
+    int heightResult = 0;
+    if (containingBlock->isBox())
+         heightResult = toRenderBox(containingBlock)->height();
+    else if (containingBlock->isRenderInline()) {
+        ASSERT(containingBlock->isRelPositioned());
+        heightResult = toRenderInline(containingBlock)->linesBoundingBox().height();
+    }
+    return heightResult - containingBlock->borderTop() - containingBlock->borderBottom();
+}
+
+void RenderBox::computePositionedLogicalWidth()
+{
+    if (isReplaced()) {
+        computePositionedLogicalWidthReplaced();
+        return;
+    }
+
+    // QUESTIONS
+    // FIXME 1: Which RenderObject's 'direction' property should used: the
+    // containing block (cb) as the spec seems to imply, the parent (parent()) as
+    // was previously done in calculating the static distances, or ourself, which
+    // was also previously done for deciding what to override when you had
+    // over-constrained margins?  Also note that the container block is used
+    // in similar situations in other parts of the RenderBox class (see computeLogicalWidth()
+    // and computeMarginsInContainingBlockInlineDirection()). For now we are using the parent for quirks
+    // mode and the containing block for strict mode.
+
+    // FIXME 2: Should we still deal with these the cases of 'left' or 'right' having
+    // the type 'static' in determining whether to calculate the static distance?
+    // NOTE: 'static' is not a legal value for 'left' or 'right' as of CSS 2.1.
+
+    // FIXME 3: Can perhaps optimize out cases when max-width/min-width are greater
+    // than or less than the computed width().  Be careful of box-sizing and
+    // percentage issues.
+
+    // The following is based off of the W3C Working Draft from April 11, 2006 of
+    // CSS 2.1: Section 10.3.7 "Absolutely positioned, non-replaced elements"
+    // <http://www.w3.org/TR/CSS21/visudet.html#abs-non-replaced-width>
+    // (block-style-comments in this function and in computePositionedLogicalWidthUsing()
+    // correspond to text from the spec)
+
+
+    // We don't use containingBlock(), since we may be positioned by an enclosing
+    // relative positioned inline.
+    const RenderBoxModelObject* containerBlock = toRenderBoxModelObject(container());
+    
+    const int containerWidth = containingBlockWidthForPositioned(containerBlock);
+
+    // To match WinIE, in quirks mode use the parent's 'direction' property
+    // instead of the the container block's.
+    TextDirection containerDirection = (document()->inQuirksMode()) ? parent()->style()->direction() : containerBlock->style()->direction();
+
+    const int bordersPlusPadding = borderAndPaddingWidth();
+    const Length marginLeft = style()->marginLeft();
+    const Length marginRight = style()->marginRight();
+    Length left = style()->left();
+    Length right = style()->right();
+
+    /*---------------------------------------------------------------------------*\
+     * For the purposes of this section and the next, the term "static position"
+     * (of an element) refers, roughly, to the position an element would have had
+     * in the normal flow. More precisely:
+     *
+     * * The static position for 'left' is the distance from the left edge of the
+     *   containing block to the left margin edge of a hypothetical box that would
+     *   have been the first box of the element if its 'position' property had
+     *   been 'static' and 'float' had been 'none'. The value is negative if the
+     *   hypothetical box is to the left of the containing block.
+     * * The static position for 'right' is the distance from the right edge of the
+     *   containing block to the right margin edge of the same hypothetical box as
+     *   above. The value is positive if the hypothetical box is to the left of the
+     *   containing block's edge.
+     *
+     * But rather than actually calculating the dimensions of that hypothetical box,
+     * user agents are free to make a guess at its probable position.
+     *
+     * For the purposes of calculating the static position, the containing block of
+     * fixed positioned elements is the initial containing block instead of the
+     * viewport, and all scrollable boxes should be assumed to be scrolled to their
+     * origin.
+    \*---------------------------------------------------------------------------*/
+
+    // see FIXME 2
+    // Calculate the static distance if needed.
+    if (left.isAuto() && right.isAuto()) {
+        if (containerDirection == LTR) {
+            // 'staticX' should already have been set through layout of the parent.
+            int staticPosition = layer()->staticX() - containerBlock->borderLeft();
+            for (RenderObject* curr = parent(); curr && curr != containerBlock; curr = curr->parent()) {
+                if (curr->isBox())
+                    staticPosition += toRenderBox(curr)->x();
+            }
+            left.setValue(Fixed, staticPosition);
+        } else {
+            RenderBox* enclosingBox = parent()->enclosingBox();
+            // 'staticX' should already have been set through layout of the parent.
+            int staticPosition = layer()->staticX() + containerWidth + containerBlock->borderRight();
+            staticPosition -= enclosingBox->width();
+            for (RenderObject* curr = enclosingBox; curr && curr != containerBlock; curr = curr->parent()) {
+                if (curr->isBox())
+                    staticPosition -= toRenderBox(curr)->x();
+            }
+            right.setValue(Fixed, staticPosition);
+        }
+    }
+
+    // Calculate constraint equation values for 'width' case.
+    int widthResult;
+    int xResult;
+    computePositionedLogicalWidthUsing(style()->width(), containerBlock, containerDirection,
+                                 containerWidth, bordersPlusPadding,
+                                 left, right, marginLeft, marginRight,
+                                 widthResult, m_marginLeft, m_marginRight, xResult);
+    setWidth(widthResult);
+    setX(xResult);
+
+    // Calculate constraint equation values for 'max-width' case.
+    if (!style()->maxWidth().isUndefined()) {
+        int maxWidth;
+        int maxMarginLeft;
+        int maxMarginRight;
+        int maxXPos;
+
+        computePositionedLogicalWidthUsing(style()->maxWidth(), containerBlock, containerDirection,
+                                     containerWidth, bordersPlusPadding,
+                                     left, right, marginLeft, marginRight,
+                                     maxWidth, maxMarginLeft, maxMarginRight, maxXPos);
+
+        if (width() > maxWidth) {
+            setWidth(maxWidth);
+            m_marginLeft = maxMarginLeft;
+            m_marginRight = maxMarginRight;
+            m_frameRect.setX(maxXPos);
+        }
+    }
+
+    // Calculate constraint equation values for 'min-width' case.
+    if (!style()->minWidth().isZero()) {
+        int minWidth;
+        int minMarginLeft;
+        int minMarginRight;
+        int minXPos;
+
+        computePositionedLogicalWidthUsing(style()->minWidth(), containerBlock, containerDirection,
+                                     containerWidth, bordersPlusPadding,
+                                     left, right, marginLeft, marginRight,
+                                     minWidth, minMarginLeft, minMarginRight, minXPos);
+
+        if (width() < minWidth) {
+            setWidth(minWidth);
+            m_marginLeft = minMarginLeft;
+            m_marginRight = minMarginRight;
+            m_frameRect.setX(minXPos);
+        }
+    }
+
+    if (stretchesToMinIntrinsicLogicalWidth() && width() < minPreferredLogicalWidth() - bordersPlusPadding) {
+        computePositionedLogicalWidthUsing(Length(minPreferredLogicalWidth() - bordersPlusPadding, Fixed), containerBlock, containerDirection,
+                                     containerWidth, bordersPlusPadding,
+                                     left, right, marginLeft, marginRight,
+                                     widthResult, m_marginLeft, m_marginRight, xResult);
+        setWidth(widthResult);
+        setX(xResult);
+    }
+
+    // Put width() into correct form.
+    setWidth(width() + bordersPlusPadding);
+}
+
+void RenderBox::computePositionedLogicalWidthUsing(Length width, const RenderBoxModelObject* containerBlock, TextDirection containerDirection,
+                                             const int containerWidth, const int bordersPlusPadding,
+                                             const Length left, const Length right, const Length marginLeft, const Length marginRight,
+                                             int& widthValue, int& marginLeftValue, int& marginRightValue, int& xPos)
+{
+    // 'left' and 'right' cannot both be 'auto' because one would of been
+    // converted to the static position already
+    ASSERT(!(left.isAuto() && right.isAuto()));
+
+    int leftValue = 0;
+
+    bool widthIsAuto = width.isIntrinsicOrAuto();
+    bool leftIsAuto = left.isAuto();
+    bool rightIsAuto = right.isAuto();
+
+    if (!leftIsAuto && !widthIsAuto && !rightIsAuto) {
+        /*-----------------------------------------------------------------------*\
+         * If none of the three is 'auto': If both 'margin-left' and 'margin-
+         * right' are 'auto', solve the equation under the extra constraint that
+         * the two margins get equal values, unless this would make them negative,
+         * in which case when direction of the containing block is 'ltr' ('rtl'),
+         * set 'margin-left' ('margin-right') to zero and solve for 'margin-right'
+         * ('margin-left'). If one of 'margin-left' or 'margin-right' is 'auto',
+         * solve the equation for that value. If the values are over-constrained,
+         * ignore the value for 'left' (in case the 'direction' property of the
+         * containing block is 'rtl') or 'right' (in case 'direction' is 'ltr')
+         * and solve for that value.
+        \*-----------------------------------------------------------------------*/
+        // NOTE:  It is not necessary to solve for 'right' in the over constrained
+        // case because the value is not used for any further calculations.
+
+        leftValue = left.calcValue(containerWidth);
+        widthValue = computeContentBoxLogicalWidth(width.calcValue(containerWidth));
+
+        const int availableSpace = containerWidth - (leftValue + widthValue + right.calcValue(containerWidth) + bordersPlusPadding);
+
+        // Margins are now the only unknown
+        if (marginLeft.isAuto() && marginRight.isAuto()) {
+            // Both margins auto, solve for equality
+            if (availableSpace >= 0) {
+                marginLeftValue = availableSpace / 2; // split the difference
+                marginRightValue = availableSpace - marginLeftValue;  // account for odd valued differences
+            } else {
+                // see FIXME 1
+                if (containerDirection == LTR) {
+                    marginLeftValue = 0;
+                    marginRightValue = availableSpace; // will be negative
+                } else {
+                    marginLeftValue = availableSpace; // will be negative
+                    marginRightValue = 0;
+                }
+            }
+        } else if (marginLeft.isAuto()) {
+            // Solve for left margin
+            marginRightValue = marginRight.calcValue(containerWidth);
+            marginLeftValue = availableSpace - marginRightValue;
+        } else if (marginRight.isAuto()) {
+            // Solve for right margin
+            marginLeftValue = marginLeft.calcValue(containerWidth);
+            marginRightValue = availableSpace - marginLeftValue;
+        } else {
+            // Over-constrained, solve for left if direction is RTL
+            marginLeftValue = marginLeft.calcValue(containerWidth);
+            marginRightValue = marginRight.calcValue(containerWidth);
+
+            // see FIXME 1 -- used to be "this->style()->direction()"
+            if (containerDirection == RTL)
+                leftValue = (availableSpace + leftValue) - marginLeftValue - marginRightValue;
+        }
+    } else {
+        /*--------------------------------------------------------------------*\
+         * Otherwise, set 'auto' values for 'margin-left' and 'margin-right'
+         * to 0, and pick the one of the following six rules that applies.
+         *
+         * 1. 'left' and 'width' are 'auto' and 'right' is not 'auto', then the
+         *    width is shrink-to-fit. Then solve for 'left'
+         *
+         *              OMIT RULE 2 AS IT SHOULD NEVER BE HIT
+         * ------------------------------------------------------------------
+         * 2. 'left' and 'right' are 'auto' and 'width' is not 'auto', then if
+         *    the 'direction' property of the containing block is 'ltr' set
+         *    'left' to the static position, otherwise set 'right' to the
+         *    static position. Then solve for 'left' (if 'direction is 'rtl')
+         *    or 'right' (if 'direction' is 'ltr').
+         * ------------------------------------------------------------------
+         *
+         * 3. 'width' and 'right' are 'auto' and 'left' is not 'auto', then the
+         *    width is shrink-to-fit . Then solve for 'right'
+         * 4. 'left' is 'auto', 'width' and 'right' are not 'auto', then solve
+         *    for 'left'
+         * 5. 'width' is 'auto', 'left' and 'right' are not 'auto', then solve
+         *    for 'width'
+         * 6. 'right' is 'auto', 'left' and 'width' are not 'auto', then solve
+         *    for 'right'
+         *
+         * Calculation of the shrink-to-fit width is similar to calculating the
+         * width of a table cell using the automatic table layout algorithm.
+         * Roughly: calculate the preferred width by formatting the content
+         * without breaking lines other than where explicit line breaks occur,
+         * and also calculate the preferred minimum width, e.g., by trying all
+         * possible line breaks. CSS 2.1 does not define the exact algorithm.
+         * Thirdly, calculate the available width: this is found by solving
+         * for 'width' after setting 'left' (in case 1) or 'right' (in case 3)
+         * to 0.
+         *
+         * Then the shrink-to-fit width is:
+         * min(max(preferred minimum width, available width), preferred width).
+        \*--------------------------------------------------------------------*/
+        // NOTE: For rules 3 and 6 it is not necessary to solve for 'right'
+        // because the value is not used for any further calculations.
+
+        // Calculate margins, 'auto' margins are ignored.
+        marginLeftValue = marginLeft.calcMinValue(containerWidth);
+        marginRightValue = marginRight.calcMinValue(containerWidth);
+
+        const int availableSpace = containerWidth - (marginLeftValue + marginRightValue + bordersPlusPadding);
+
+        // FIXME: Is there a faster way to find the correct case?
+        // Use rule/case that applies.
+        if (leftIsAuto && widthIsAuto && !rightIsAuto) {
+            // RULE 1: (use shrink-to-fit for width, and solve of left)
+            int rightValue = right.calcValue(containerWidth);
+
+            // FIXME: would it be better to have shrink-to-fit in one step?
+            int preferredWidth = maxPreferredLogicalWidth() - bordersPlusPadding;
+            int preferredMinWidth = minPreferredLogicalWidth() - bordersPlusPadding;
+            int availableWidth = availableSpace - rightValue;
+            widthValue = min(max(preferredMinWidth, availableWidth), preferredWidth);
+            leftValue = availableSpace - (widthValue + rightValue);
+        } else if (!leftIsAuto && widthIsAuto && rightIsAuto) {
+            // RULE 3: (use shrink-to-fit for width, and no need solve of right)
+            leftValue = left.calcValue(containerWidth);
+
+            // FIXME: would it be better to have shrink-to-fit in one step?
+            int preferredWidth = maxPreferredLogicalWidth() - bordersPlusPadding;
+            int preferredMinWidth = minPreferredLogicalWidth() - bordersPlusPadding;
+            int availableWidth = availableSpace - leftValue;
+            widthValue = min(max(preferredMinWidth, availableWidth), preferredWidth);
+        } else if (leftIsAuto && !width.isAuto() && !rightIsAuto) {
+            // RULE 4: (solve for left)
+            widthValue = computeContentBoxLogicalWidth(width.calcValue(containerWidth));
+            leftValue = availableSpace - (widthValue + right.calcValue(containerWidth));
+        } else if (!leftIsAuto && widthIsAuto && !rightIsAuto) {
+            // RULE 5: (solve for width)
+            leftValue = left.calcValue(containerWidth);
+            widthValue = availableSpace - (leftValue + right.calcValue(containerWidth));
+        } else if (!leftIsAuto&& !widthIsAuto && rightIsAuto) {
+            // RULE 6: (no need solve for right)
+            leftValue = left.calcValue(containerWidth);
+            widthValue = computeContentBoxLogicalWidth(width.calcValue(containerWidth));
+        }
+    }
+
+    // Use computed values to calculate the horizontal position.
+
+    // FIXME: This hack is needed to calculate the xPos for a 'rtl' relatively
+    // positioned, inline because right now, it is using the xPos
+    // of the first line box when really it should use the last line box.  When
+    // this is fixed elsewhere, this block should be removed.
+    if (containerBlock->isRenderInline() && !containerBlock->style()->isLeftToRightDirection()) {
+        const RenderInline* flow = toRenderInline(containerBlock);
+        InlineFlowBox* firstLine = flow->firstLineBox();
+        InlineFlowBox* lastLine = flow->lastLineBox();
+        if (firstLine && lastLine && firstLine != lastLine) {
+            xPos = leftValue + marginLeftValue + lastLine->borderLogicalLeft() + (lastLine->x() - firstLine->x());
+            return;
+        }
+    }
+
+    xPos = leftValue + marginLeftValue + containerBlock->borderLeft();
+}
+
+void RenderBox::computePositionedLogicalHeight()
+{
+    if (isReplaced()) {
+        computePositionedLogicalHeightReplaced();
+        return;
+    }
+
+    // The following is based off of the W3C Working Draft from April 11, 2006 of
+    // CSS 2.1: Section 10.6.4 "Absolutely positioned, non-replaced elements"
+    // <http://www.w3.org/TR/2005/WD-CSS21-20050613/visudet.html#abs-non-replaced-height>
+    // (block-style-comments in this function and in computePositionedLogicalHeightUsing()
+    // correspond to text from the spec)
+
+
+    // We don't use containingBlock(), since we may be positioned by an enclosing relpositioned inline.
+    const RenderBoxModelObject* containerBlock = toRenderBoxModelObject(container());
+
+    const int containerHeight = containingBlockHeightForPositioned(containerBlock);
+
+    const int bordersPlusPadding = borderAndPaddingHeight();
+    const Length marginTop = style()->marginTop();
+    const Length marginBottom = style()->marginBottom();
+    Length top = style()->top();
+    Length bottom = style()->bottom();
+
+    /*---------------------------------------------------------------------------*\
+     * For the purposes of this section and the next, the term "static position"
+     * (of an element) refers, roughly, to the position an element would have had
+     * in the normal flow. More precisely, the static position for 'top' is the
+     * distance from the top edge of the containing block to the top margin edge
+     * of a hypothetical box that would have been the first box of the element if
+     * its 'position' property had been 'static' and 'float' had been 'none'. The
+     * value is negative if the hypothetical box is above the containing block.
+     *
+     * But rather than actually calculating the dimensions of that hypothetical
+     * box, user agents are free to make a guess at its probable position.
+     *
+     * For the purposes of calculating the static position, the containing block
+     * of fixed positioned elements is the initial containing block instead of
+     * the viewport.
+    \*---------------------------------------------------------------------------*/
+
+    // see FIXME 2
+    // Calculate the static distance if needed.
+    if (top.isAuto() && bottom.isAuto()) {
+        // staticY should already have been set through layout of the parent()
+        int staticTop = layer()->staticY() - containerBlock->borderTop();
+        for (RenderObject* po = parent(); po && po != containerBlock; po = po->parent()) {
+            if (po->isBox() && !po->isTableRow())
+                staticTop += toRenderBox(po)->y();
+        }
+        top.setValue(Fixed, staticTop);
+    }
+
+
+    int h; // Needed to compute overflow.
+    int y;
+
+    // Calculate constraint equation values for 'height' case.
+    computePositionedLogicalHeightUsing(style()->height(), containerBlock, containerHeight, bordersPlusPadding,
+                               top, bottom, marginTop, marginBottom,
+                               h, m_marginTop, m_marginBottom, y);
+    setY(y);
+
+    // Avoid doing any work in the common case (where the values of min-height and max-height are their defaults).
+    // see FIXME 3
+
+    // Calculate constraint equation values for 'max-height' case.
+    if (!style()->maxHeight().isUndefined()) {
+        int maxHeight;
+        int maxMarginTop;
+        int maxMarginBottom;
+        int maxYPos;
+
+        computePositionedLogicalHeightUsing(style()->maxHeight(), containerBlock, containerHeight, bordersPlusPadding,
+                                   top, bottom, marginTop, marginBottom,
+                                   maxHeight, maxMarginTop, maxMarginBottom, maxYPos);
+
+        if (h > maxHeight) {
+            h = maxHeight;
+            m_marginTop = maxMarginTop;
+            m_marginBottom = maxMarginBottom;
+            m_frameRect.setY(maxYPos);
+        }
+    }
+
+    // Calculate constraint equation values for 'min-height' case.
+    if (!style()->minHeight().isZero()) {
+        int minHeight;
+        int minMarginTop;
+        int minMarginBottom;
+        int minYPos;
+
+        computePositionedLogicalHeightUsing(style()->minHeight(), containerBlock, containerHeight, bordersPlusPadding,
+                                   top, bottom, marginTop, marginBottom,
+                                   minHeight, minMarginTop, minMarginBottom, minYPos);
+
+        if (h < minHeight) {
+            h = minHeight;
+            m_marginTop = minMarginTop;
+            m_marginBottom = minMarginBottom;
+            m_frameRect.setY(minYPos);
+        }
+    }
+
+    // Set final height value.
+    setHeight(h + bordersPlusPadding);
+}
+
+void RenderBox::computePositionedLogicalHeightUsing(Length h, const RenderBoxModelObject* containerBlock,
+                                           const int containerHeight, const int bordersPlusPadding,
+                                           const Length top, const Length bottom, const Length marginTop, const Length marginBottom,
+                                           int& heightValue, int& marginTopValue, int& marginBottomValue, int& yPos)
+{
+    // 'top' and 'bottom' cannot both be 'auto' because 'top would of been
+    // converted to the static position in computePositionedLogicalHeight()
+    ASSERT(!(top.isAuto() && bottom.isAuto()));
+
+    int contentHeight = height() - bordersPlusPadding;
+
+    int topValue = 0;
+
+    bool heightIsAuto = h.isAuto();
+    bool topIsAuto = top.isAuto();
+    bool bottomIsAuto = bottom.isAuto();
+
+    // Height is never unsolved for tables.
+    if (isTable()) {
+        h.setValue(Fixed, contentHeight);
+        heightIsAuto = false;
+    }
+
+    if (!topIsAuto && !heightIsAuto && !bottomIsAuto) {
+        /*-----------------------------------------------------------------------*\
+         * If none of the three are 'auto': If both 'margin-top' and 'margin-
+         * bottom' are 'auto', solve the equation under the extra constraint that
+         * the two margins get equal values. If one of 'margin-top' or 'margin-
+         * bottom' is 'auto', solve the equation for that value. If the values
+         * are over-constrained, ignore the value for 'bottom' and solve for that
+         * value.
+        \*-----------------------------------------------------------------------*/
+        // NOTE:  It is not necessary to solve for 'bottom' in the over constrained
+        // case because the value is not used for any further calculations.
+
+        heightValue = computeContentBoxLogicalHeight(h.calcValue(containerHeight));
+        topValue = top.calcValue(containerHeight);
+
+        const int availableSpace = containerHeight - (topValue + heightValue + bottom.calcValue(containerHeight) + bordersPlusPadding);
+
+        // Margins are now the only unknown
+        if (marginTop.isAuto() && marginBottom.isAuto()) {
+            // Both margins auto, solve for equality
+            // NOTE: This may result in negative values.
+            marginTopValue = availableSpace / 2; // split the difference
+            marginBottomValue = availableSpace - marginTopValue; // account for odd valued differences
+        } else if (marginTop.isAuto()) {
+            // Solve for top margin
+            marginBottomValue = marginBottom.calcValue(containerHeight);
+            marginTopValue = availableSpace - marginBottomValue;
+        } else if (marginBottom.isAuto()) {
+            // Solve for bottom margin
+            marginTopValue = marginTop.calcValue(containerHeight);
+            marginBottomValue = availableSpace - marginTopValue;
+        } else {
+            // Over-constrained, (no need solve for bottom)
+            marginTopValue = marginTop.calcValue(containerHeight);
+            marginBottomValue = marginBottom.calcValue(containerHeight);
+        }
+    } else {
+        /*--------------------------------------------------------------------*\
+         * Otherwise, set 'auto' values for 'margin-top' and 'margin-bottom'
+         * to 0, and pick the one of the following six rules that applies.
+         *
+         * 1. 'top' and 'height' are 'auto' and 'bottom' is not 'auto', then
+         *    the height is based on the content, and solve for 'top'.
+         *
+         *              OMIT RULE 2 AS IT SHOULD NEVER BE HIT
+         * ------------------------------------------------------------------
+         * 2. 'top' and 'bottom' are 'auto' and 'height' is not 'auto', then
+         *    set 'top' to the static position, and solve for 'bottom'.
+         * ------------------------------------------------------------------
+         *
+         * 3. 'height' and 'bottom' are 'auto' and 'top' is not 'auto', then
+         *    the height is based on the content, and solve for 'bottom'.
+         * 4. 'top' is 'auto', 'height' and 'bottom' are not 'auto', and
+         *    solve for 'top'.
+         * 5. 'height' is 'auto', 'top' and 'bottom' are not 'auto', and
+         *    solve for 'height'.
+         * 6. 'bottom' is 'auto', 'top' and 'height' are not 'auto', and
+         *    solve for 'bottom'.
+        \*--------------------------------------------------------------------*/
+        // NOTE: For rules 3 and 6 it is not necessary to solve for 'bottom'
+        // because the value is not used for any further calculations.
+
+        // Calculate margins, 'auto' margins are ignored.
+        marginTopValue = marginTop.calcMinValue(containerHeight);
+        marginBottomValue = marginBottom.calcMinValue(containerHeight);
+
+        const int availableSpace = containerHeight - (marginTopValue + marginBottomValue + bordersPlusPadding);
+
+        // Use rule/case that applies.
+        if (topIsAuto && heightIsAuto && !bottomIsAuto) {
+            // RULE 1: (height is content based, solve of top)
+            heightValue = contentHeight;
+            topValue = availableSpace - (heightValue + bottom.calcValue(containerHeight));
+        } else if (!topIsAuto && heightIsAuto && bottomIsAuto) {
+            // RULE 3: (height is content based, no need solve of bottom)
+            topValue = top.calcValue(containerHeight);
+            heightValue = contentHeight;
+        } else if (topIsAuto && !heightIsAuto && !bottomIsAuto) {
+            // RULE 4: (solve of top)
+            heightValue = computeContentBoxLogicalHeight(h.calcValue(containerHeight));
+            topValue = availableSpace - (heightValue + bottom.calcValue(containerHeight));
+        } else if (!topIsAuto && heightIsAuto && !bottomIsAuto) {
+            // RULE 5: (solve of height)
+            topValue = top.calcValue(containerHeight);
+            heightValue = max(0, availableSpace - (topValue + bottom.calcValue(containerHeight)));
+        } else if (!topIsAuto && !heightIsAuto && bottomIsAuto) {
+            // RULE 6: (no need solve of bottom)
+            heightValue = computeContentBoxLogicalHeight(h.calcValue(containerHeight));
+            topValue = top.calcValue(containerHeight);
+        }
+    }
+
+    // Use computed values to calculate the vertical position.
+    yPos = topValue + marginTopValue + containerBlock->borderTop();
+}
+
+void RenderBox::computePositionedLogicalWidthReplaced()
+{
+    // The following is based off of the W3C Working Draft from April 11, 2006 of
+    // CSS 2.1: Section 10.3.8 "Absolutely positioned, replaced elements"
+    // <http://www.w3.org/TR/2005/WD-CSS21-20050613/visudet.html#abs-replaced-width>
+    // (block-style-comments in this function correspond to text from the spec and
+    // the numbers correspond to numbers in spec)
+
+    // We don't use containingBlock(), since we may be positioned by an enclosing
+    // relative positioned inline.
+    const RenderBoxModelObject* containerBlock = toRenderBoxModelObject(container());
+
+    const int containerWidth = containingBlockWidthForPositioned(containerBlock);
+
+    // To match WinIE, in quirks mode use the parent's 'direction' property
+    // instead of the the container block's.
+    TextDirection containerDirection = (document()->inQuirksMode()) ? parent()->style()->direction() : containerBlock->style()->direction();
+
+    // Variables to solve.
+    Length left = style()->left();
+    Length right = style()->right();
+    Length marginLeft = style()->marginLeft();
+    Length marginRight = style()->marginRight();
+
+
+    /*-----------------------------------------------------------------------*\
+     * 1. The used value of 'width' is determined as for inline replaced
+     *    elements.
+    \*-----------------------------------------------------------------------*/
+    // NOTE: This value of width is FINAL in that the min/max width calculations
+    // are dealt with in computeReplacedWidth().  This means that the steps to produce
+    // correct max/min in the non-replaced version, are not necessary.
+    setWidth(computeReplacedLogicalWidth() + borderAndPaddingWidth());
+    const int availableSpace = containerWidth - width();
+
+    /*-----------------------------------------------------------------------*\
+     * 2. If both 'left' and 'right' have the value 'auto', then if 'direction'
+     *    of the containing block is 'ltr', set 'left' to the static position;
+     *    else if 'direction' is 'rtl', set 'right' to the static position.
+    \*-----------------------------------------------------------------------*/
+    // see FIXME 2
+    if (left.isAuto() && right.isAuto()) {
+        // see FIXME 1
+        if (containerDirection == LTR) {
+            // 'staticX' should already have been set through layout of the parent.
+            int staticPosition = layer()->staticX() - containerBlock->borderLeft();
+            for (RenderObject* po = parent(); po && po != containerBlock; po = po->parent()) {
+                if (po->isBox())
+                    staticPosition += toRenderBox(po)->x();
+            }
+            left.setValue(Fixed, staticPosition);
+        } else {
+            RenderObject* po = parent();
+            // 'staticX' should already have been set through layout of the parent.
+            int staticPosition = layer()->staticX() + containerWidth + containerBlock->borderRight();
+            for ( ; po && po != containerBlock; po = po->parent()) {
+                if (po->isBox())
+                    staticPosition += toRenderBox(po)->x();
+            }
+            right.setValue(Fixed, staticPosition);
+        }
+    }
+
+    /*-----------------------------------------------------------------------*\
+     * 3. If 'left' or 'right' are 'auto', replace any 'auto' on 'margin-left'
+     *    or 'margin-right' with '0'.
+    \*-----------------------------------------------------------------------*/
+    if (left.isAuto() || right.isAuto()) {
+        if (marginLeft.isAuto())
+            marginLeft.setValue(Fixed, 0);
+        if (marginRight.isAuto())
+            marginRight.setValue(Fixed, 0);
+    }
+
+    /*-----------------------------------------------------------------------*\
+     * 4. If at this point both 'margin-left' and 'margin-right' are still
+     *    'auto', solve the equation under the extra constraint that the two
+     *    margins must get equal values, unless this would make them negative,
+     *    in which case when the direction of the containing block is 'ltr'
+     *    ('rtl'), set 'margin-left' ('margin-right') to zero and solve for
+     *    'margin-right' ('margin-left').
+    \*-----------------------------------------------------------------------*/
+    int leftValue = 0;
+    int rightValue = 0;
+
+    if (marginLeft.isAuto() && marginRight.isAuto()) {
+        // 'left' and 'right' cannot be 'auto' due to step 3
+        ASSERT(!(left.isAuto() && right.isAuto()));
+
+        leftValue = left.calcValue(containerWidth);
+        rightValue = right.calcValue(containerWidth);
+
+        int difference = availableSpace - (leftValue + rightValue);
+        if (difference > 0) {
+            m_marginLeft = difference / 2; // split the difference
+            m_marginRight = difference - m_marginLeft; // account for odd valued differences
+        } else {
+            // see FIXME 1
+            if (containerDirection == LTR) {
+                m_marginLeft = 0;
+                m_marginRight = difference;  // will be negative
+            } else {
+                m_marginLeft = difference;  // will be negative
+                m_marginRight = 0;
+            }
+        }
+
+    /*-----------------------------------------------------------------------*\
+     * 5. If at this point there is an 'auto' left, solve the equation for
+     *    that value.
+    \*-----------------------------------------------------------------------*/
+    } else if (left.isAuto()) {
+        m_marginLeft = marginLeft.calcValue(containerWidth);
+        m_marginRight = marginRight.calcValue(containerWidth);
+        rightValue = right.calcValue(containerWidth);
+
+        // Solve for 'left'
+        leftValue = availableSpace - (rightValue + m_marginLeft + m_marginRight);
+    } else if (right.isAuto()) {
+        m_marginLeft = marginLeft.calcValue(containerWidth);
+        m_marginRight = marginRight.calcValue(containerWidth);
+        leftValue = left.calcValue(containerWidth);
+
+        // Solve for 'right'
+        rightValue = availableSpace - (leftValue + m_marginLeft + m_marginRight);
+    } else if (marginLeft.isAuto()) {
+        m_marginRight = marginRight.calcValue(containerWidth);
+        leftValue = left.calcValue(containerWidth);
+        rightValue = right.calcValue(containerWidth);
+
+        // Solve for 'margin-left'
+        m_marginLeft = availableSpace - (leftValue + rightValue + m_marginRight);
+    } else if (marginRight.isAuto()) {
+        m_marginLeft = marginLeft.calcValue(containerWidth);
+        leftValue = left.calcValue(containerWidth);
+        rightValue = right.calcValue(containerWidth);
+
+        // Solve for 'margin-right'
+        m_marginRight = availableSpace - (leftValue + rightValue + m_marginLeft);
+    } else {
+        // Nothing is 'auto', just calculate the values.
+        m_marginLeft = marginLeft.calcValue(containerWidth);
+        m_marginRight = marginRight.calcValue(containerWidth);
+        rightValue = right.calcValue(containerWidth);
+        leftValue = left.calcValue(containerWidth);
+    }
+
+    /*-----------------------------------------------------------------------*\
+     * 6. If at this point the values are over-constrained, ignore the value
+     *    for either 'left' (in case the 'direction' property of the
+     *    containing block is 'rtl') or 'right' (in case 'direction' is
+     *    'ltr') and solve for that value.
+    \*-----------------------------------------------------------------------*/
+    // NOTE:  It is not necessary to solve for 'right' when the direction is
+    // LTR because the value is not used.
+    int totalWidth = width() + leftValue + rightValue +  m_marginLeft + m_marginRight;
+    if (totalWidth > containerWidth && (containerDirection == RTL))
+        leftValue = containerWidth - (totalWidth - leftValue);
+
+    // Use computed values to calculate the horizontal position.
+
+    // FIXME: This hack is needed to calculate the xPos for a 'rtl' relatively
+    // positioned, inline containing block because right now, it is using the xPos
+    // of the first line box when really it should use the last line box.  When
+    // this is fixed elsewhere, this block should be removed.
+    if (containerBlock->isRenderInline() && !containerBlock->style()->isLeftToRightDirection()) {
+        const RenderInline* flow = toRenderInline(containerBlock);
+        InlineFlowBox* firstLine = flow->firstLineBox();
+        InlineFlowBox* lastLine = flow->lastLineBox();
+        if (firstLine && lastLine && firstLine != lastLine) {
+            m_frameRect.setX(leftValue + m_marginLeft + lastLine->borderLogicalLeft() + (lastLine->x() - firstLine->x()));
+            return;
+        }
+    }
+
+    m_frameRect.setX(leftValue + m_marginLeft + containerBlock->borderLeft());
+}
+
+void RenderBox::computePositionedLogicalHeightReplaced()
+{
+    // The following is based off of the W3C Working Draft from April 11, 2006 of
+    // CSS 2.1: Section 10.6.5 "Absolutely positioned, replaced elements"
+    // <http://www.w3.org/TR/2005/WD-CSS21-20050613/visudet.html#abs-replaced-height>
+    // (block-style-comments in this function correspond to text from the spec and
+    // the numbers correspond to numbers in spec)
+
+    // We don't use containingBlock(), since we may be positioned by an enclosing relpositioned inline.
+    const RenderBoxModelObject* containerBlock = toRenderBoxModelObject(container());
+
+    const int containerHeight = containingBlockHeightForPositioned(containerBlock);
+
+    // Variables to solve.
+    Length top = style()->top();
+    Length bottom = style()->bottom();
+    Length marginTop = style()->marginTop();
+    Length marginBottom = style()->marginBottom();
+
+
+    /*-----------------------------------------------------------------------*\
+     * 1. The used value of 'height' is determined as for inline replaced
+     *    elements.
+    \*-----------------------------------------------------------------------*/
+    // NOTE: This value of height is FINAL in that the min/max height calculations
+    // are dealt with in computeReplacedHeight().  This means that the steps to produce
+    // correct max/min in the non-replaced version, are not necessary.
+    setHeight(computeReplacedLogicalHeight() + borderAndPaddingHeight());
+    const int availableSpace = containerHeight - height();
+
+    /*-----------------------------------------------------------------------*\
+     * 2. If both 'top' and 'bottom' have the value 'auto', replace 'top'
+     *    with the element's static position.
+    \*-----------------------------------------------------------------------*/
+    // see FIXME 2
+    if (top.isAuto() && bottom.isAuto()) {
+        // staticY should already have been set through layout of the parent().
+        int staticTop = layer()->staticY() - containerBlock->borderTop();
+        for (RenderObject* po = parent(); po && po != containerBlock; po = po->parent()) {
+            if (po->isBox() && !po->isTableRow())
+                staticTop += toRenderBox(po)->y();
+        }
+        top.setValue(Fixed, staticTop);
+    }
+
+    /*-----------------------------------------------------------------------*\
+     * 3. If 'bottom' is 'auto', replace any 'auto' on 'margin-top' or
+     *    'margin-bottom' with '0'.
+    \*-----------------------------------------------------------------------*/
+    // FIXME: The spec. says that this step should only be taken when bottom is
+    // auto, but if only top is auto, this makes step 4 impossible.
+    if (top.isAuto() || bottom.isAuto()) {
+        if (marginTop.isAuto())
+            marginTop.setValue(Fixed, 0);
+        if (marginBottom.isAuto())
+            marginBottom.setValue(Fixed, 0);
+    }
+
+    /*-----------------------------------------------------------------------*\
+     * 4. If at this point both 'margin-top' and 'margin-bottom' are still
+     *    'auto', solve the equation under the extra constraint that the two
+     *    margins must get equal values.
+    \*-----------------------------------------------------------------------*/
+    int topValue = 0;
+    int bottomValue = 0;
+
+    if (marginTop.isAuto() && marginBottom.isAuto()) {
+        // 'top' and 'bottom' cannot be 'auto' due to step 2 and 3 combined.
+        ASSERT(!(top.isAuto() || bottom.isAuto()));
+
+        topValue = top.calcValue(containerHeight);
+        bottomValue = bottom.calcValue(containerHeight);
+
+        int difference = availableSpace - (topValue + bottomValue);
+        // NOTE: This may result in negative values.
+        m_marginTop =  difference / 2; // split the difference
+        m_marginBottom = difference - m_marginTop; // account for odd valued differences
+
+    /*-----------------------------------------------------------------------*\
+     * 5. If at this point there is only one 'auto' left, solve the equation
+     *    for that value.
+    \*-----------------------------------------------------------------------*/
+    } else if (top.isAuto()) {
+        m_marginTop = marginTop.calcValue(containerHeight);
+        m_marginBottom = marginBottom.calcValue(containerHeight);
+        bottomValue = bottom.calcValue(containerHeight);
+
+        // Solve for 'top'
+        topValue = availableSpace - (bottomValue + m_marginTop + m_marginBottom);
+    } else if (bottom.isAuto()) {
+        m_marginTop = marginTop.calcValue(containerHeight);
+        m_marginBottom = marginBottom.calcValue(containerHeight);
+        topValue = top.calcValue(containerHeight);
+
+        // Solve for 'bottom'
+        // NOTE: It is not necessary to solve for 'bottom' because we don't ever
+        // use the value.
+    } else if (marginTop.isAuto()) {
+        m_marginBottom = marginBottom.calcValue(containerHeight);
+        topValue = top.calcValue(containerHeight);
+        bottomValue = bottom.calcValue(containerHeight);
+
+        // Solve for 'margin-top'
+        m_marginTop = availableSpace - (topValue + bottomValue + m_marginBottom);
+    } else if (marginBottom.isAuto()) {
+        m_marginTop = marginTop.calcValue(containerHeight);
+        topValue = top.calcValue(containerHeight);
+        bottomValue = bottom.calcValue(containerHeight);
+
+        // Solve for 'margin-bottom'
+        m_marginBottom = availableSpace - (topValue + bottomValue + m_marginTop);
+    } else {
+        // Nothing is 'auto', just calculate the values.
+        m_marginTop = marginTop.calcValue(containerHeight);
+        m_marginBottom = marginBottom.calcValue(containerHeight);
+        topValue = top.calcValue(containerHeight);
+        // NOTE: It is not necessary to solve for 'bottom' because we don't ever
+        // use the value.
+     }
+
+    /*-----------------------------------------------------------------------*\
+     * 6. If at this point the values are over-constrained, ignore the value
+     *    for 'bottom' and solve for that value.
+    \*-----------------------------------------------------------------------*/
+    // NOTE: It is not necessary to do this step because we don't end up using
+    // the value of 'bottom' regardless of whether the values are over-constrained
+    // or not.
+
+    // Use computed values to calculate the vertical position.
+    m_frameRect.setY(topValue + m_marginTop + containerBlock->borderTop());
+}
+
+IntRect RenderBox::localCaretRect(InlineBox* box, int caretOffset, int* extraWidthToEndOfLine)
+{
+    // VisiblePositions at offsets inside containers either a) refer to the positions before/after
+    // those containers (tables and select elements) or b) refer to the position inside an empty block.
+    // They never refer to children.
+    // FIXME: Paint the carets inside empty blocks differently than the carets before/after elements.
+
+    // FIXME: What about border and padding?
+    IntRect rect(x(), y(), caretWidth, height());
+    bool ltr = box ? box->isLeftToRightDirection() : style()->isLeftToRightDirection();
+
+    if ((!caretOffset) ^ ltr)
+        rect.move(IntSize(width() - caretWidth, 0));
+
+    if (box) {
+        RootInlineBox* rootBox = box->root();
+        int top = rootBox->lineTop();
+        rect.setY(top);
+        rect.setHeight(rootBox->lineBottom() - top);
+    }
+
+    // If height of box is smaller than font height, use the latter one,
+    // otherwise the caret might become invisible.
+    //
+    // Also, if the box is not a replaced element, always use the font height.
+    // This prevents the "big caret" bug described in:
+    // <rdar://problem/3777804> Deleting all content in a document can result in giant tall-as-window insertion point
+    //
+    // FIXME: ignoring :first-line, missing good reason to take care of
+    int fontHeight = style()->font().height();
+    if (fontHeight > rect.height() || (!isReplaced() && !isTable()))
+        rect.setHeight(fontHeight);
+
+    if (extraWidthToEndOfLine)
+        *extraWidthToEndOfLine = x() + width() - rect.right();
+
+    // Move to local coords
+    rect.move(-x(), -y());
+    return rect;
+}
+
+VisiblePosition RenderBox::positionForPoint(const IntPoint& point)
+{
+    // no children...return this render object's element, if there is one, and offset 0
+    if (!firstChild())
+        return createVisiblePosition(node() ? firstDeepEditingPositionForNode(node()) : Position(0, 0));
+
+    int xPos = point.x();
+    int yPos = point.y();
+
+    if (isTable() && node()) {
+        int right = contentWidth() + borderAndPaddingWidth();
+        int bottom = contentHeight() + borderAndPaddingHeight();
+        
+        if (xPos < 0 || xPos > right || yPos < 0 || yPos > bottom) {
+            if (xPos <= right / 2)
+                return createVisiblePosition(firstDeepEditingPositionForNode(node()));
+            return createVisiblePosition(lastDeepEditingPositionForNode(node()));
+        }
+    }
+
+    // Pass off to the closest child.
+    int minDist = INT_MAX;
+    RenderBox* closestRenderer = 0;
+    int newX = xPos;
+    int newY = yPos;
+    if (isTableRow()) {
+        newX += x();
+        newY += y();
+    }
+    for (RenderObject* renderObject = firstChild(); renderObject; renderObject = renderObject->nextSibling()) {
+        if ((!renderObject->firstChild() && !renderObject->isInline() && !renderObject->isBlockFlow() )
+            || renderObject->style()->visibility() != VISIBLE)
+            continue;
+        
+        if (!renderObject->isBox())
+            continue;
+        
+        RenderBox* renderer = toRenderBox(renderObject);
+
+        int top = renderer->borderTop() + renderer->paddingTop() + (isTableRow() ? 0 : renderer->y());
+        int bottom = top + renderer->contentHeight();
+        int left = renderer->borderLeft() + renderer->paddingLeft() + (isTableRow() ? 0 : renderer->x());
+        int right = left + renderer->contentWidth();
+        
+        if (xPos <= right && xPos >= left && yPos <= top && yPos >= bottom) {
+            if (renderer->isTableRow())
+                return renderer->positionForCoordinates(xPos + newX - renderer->x(), yPos + newY - renderer->y());
+            return renderer->positionForCoordinates(xPos - renderer->x(), yPos - renderer->y());
+        }
+
+        // Find the distance from (x, y) to the box.  Split the space around the box into 8 pieces
+        // and use a different compare depending on which piece (x, y) is in.
+        IntPoint cmp;
+        if (xPos > right) {
+            if (yPos < top)
+                cmp = IntPoint(right, top);
+            else if (yPos > bottom)
+                cmp = IntPoint(right, bottom);
+            else
+                cmp = IntPoint(right, yPos);
+        } else if (xPos < left) {
+            if (yPos < top)
+                cmp = IntPoint(left, top);
+            else if (yPos > bottom)
+                cmp = IntPoint(left, bottom);
+            else
+                cmp = IntPoint(left, yPos);
+        } else {
+            if (yPos < top)
+                cmp = IntPoint(xPos, top);
+            else
+                cmp = IntPoint(xPos, bottom);
+        }
+        
+        int x1minusx2 = cmp.x() - xPos;
+        int y1minusy2 = cmp.y() - yPos;
+        
+        int dist = x1minusx2 * x1minusx2 + y1minusy2 * y1minusy2;
+        if (dist < minDist) {
+            closestRenderer = renderer;
+            minDist = dist;
+        }
+    }
+    
+    if (closestRenderer)
+        return closestRenderer->positionForCoordinates(newX - closestRenderer->x(), newY - closestRenderer->y());
+    
+    return createVisiblePosition(firstDeepEditingPositionForNode(node()));
+}
+
+bool RenderBox::shrinkToAvoidFloats() const
+{
+    // FIXME: Technically we should be able to shrink replaced elements on a line, but this is difficult to accomplish, since this
+    // involves doing a relayout during findNextLineBreak and somehow overriding the containingBlockWidth method to return the
+    // current remaining width on a line.
+    if ((isInline() && !isHTMLMarquee()) || !avoidsFloats())
+        return false;
+
+    // All auto-width objects that avoid floats should always use lineWidth.
+    return style()->width().isAuto();
+}
+
+bool RenderBox::avoidsFloats() const
+{
+    return isReplaced() || hasOverflowClip() || isHR() || isLegend() || isWritingModeRoot();
+}
+
+void RenderBox::addShadowOverflow()
+{
+    int shadowLeft;
+    int shadowRight;
+    int shadowTop;
+    int shadowBottom;
+    style()->getBoxShadowExtent(shadowTop, shadowRight, shadowBottom, shadowLeft);
+    IntRect borderBox = borderBoxRect();
+    int overflowLeft = borderBox.x() + shadowLeft;
+    int overflowRight = borderBox.right() + shadowRight;
+    int overflowTop = borderBox.y() + shadowTop;
+    int overflowBottom = borderBox.bottom() + shadowBottom;
+    addVisualOverflow(IntRect(overflowLeft, overflowTop, overflowRight - overflowLeft, overflowBottom - overflowTop));
+}
+
+void RenderBox::addOverflowFromChild(RenderBox* child, const IntSize& delta)
+{
+    // Only propagate layout overflow from the child if the child isn't clipping its overflow.  If it is, then
+    // its overflow is internal to it, and we don't care about it.  layoutOverflowRectForPropagation takes care of this
+    // and just propagates the border box rect instead.
+    IntRect childLayoutOverflowRect = child->layoutOverflowRectForPropagation(style());
+    childLayoutOverflowRect.move(delta);
+    addLayoutOverflow(childLayoutOverflowRect);
+            
+    // Add in visual overflow from the child.  Even if the child clips its overflow, it may still
+    // have visual overflow of its own set from box shadows or reflections.  It is unnecessary to propagate this
+    // overflow if we are clipping our own overflow.
+    if (child->hasSelfPaintingLayer() || hasOverflowClip())
+        return;
+    IntRect childVisualOverflowRect = child->visualOverflowRectForPropagation(style());
+    childVisualOverflowRect.move(delta);
+    addVisualOverflow(childVisualOverflowRect);
+}
+
+void RenderBox::addLayoutOverflow(const IntRect& rect)
+{
+    IntRect clientBox = clientBoxRect();
+    if (clientBox.contains(rect) || rect.isEmpty())
+        return;
+    
+    // For overflow clip objects, we don't want to propagate overflow into unreachable areas.
+    IntRect overflowRect(rect);
+    if (hasOverflowClip() || isRenderView()) {
+        // Overflow is in the block's coordinate space and thus is flipped for horizontal-bt and vertical-rl 
+        // writing modes.  At this stage that is actually a simplification, since we can treat horizontal-tb/bt as the same
+        // and vertical-lr/rl as the same.
+        bool hasTopOverflow = !style()->isLeftToRightDirection() && !style()->isHorizontalWritingMode();
+        bool hasLeftOverflow = !style()->isLeftToRightDirection() && style()->isHorizontalWritingMode();
+        
+        if (!hasTopOverflow)
+            overflowRect.shiftTopEdgeTo(max(overflowRect.y(), clientBox.y()));
+        else
+            overflowRect.shiftBottomEdgeTo(min(overflowRect.bottom(), clientBox.bottom()));
+        if (!hasLeftOverflow)
+            overflowRect.shiftLeftEdgeTo(max(overflowRect.x(), clientBox.x()));
+        else
+            overflowRect.shiftRightEdgeTo(min(overflowRect.right(), clientBox.right()));
+        
+        // Now re-test with the adjusted rectangle and see if it has become unreachable or fully
+        // contained.
+        if (clientBox.contains(overflowRect) || overflowRect.isEmpty())
+            return;
+    }
+
+    if (!m_overflow)
+        m_overflow.set(new RenderOverflow(clientBox, borderBoxRect()));
+    
+    m_overflow->addLayoutOverflow(overflowRect);
+}
+
+void RenderBox::addVisualOverflow(const IntRect& rect)
+{
+    IntRect borderBox = borderBoxRect();
+    if (borderBox.contains(rect) || rect.isEmpty())
+        return;
+        
+    if (!m_overflow)
+        m_overflow.set(new RenderOverflow(clientBoxRect(), borderBox));
+    
+    m_overflow->addVisualOverflow(rect);
+}
+
+void RenderBox::clearLayoutOverflow()
+{
+    if (!m_overflow)
+        return;
+    
+    if (visualOverflowRect() == borderBoxRect()) {
+        m_overflow.clear();
+        return;
+    }
+    
+    m_overflow->resetLayoutOverflow(borderBoxRect());
+}
+
+int RenderBox::lineHeight(bool /*firstLine*/, LineDirectionMode direction, LinePositionMode /*linePositionMode*/) const
+{
+    if (isReplaced())
+        return direction == HorizontalLine ? m_marginTop + height() + m_marginBottom : m_marginRight + width() + m_marginLeft;
+    return 0;
+}
+
+int RenderBox::baselinePosition(FontBaseline baselineType, bool /*firstLine*/, LineDirectionMode direction, LinePositionMode /*linePositionMode*/) const
+{
+    if (isReplaced()) {
+        int result = direction == HorizontalLine ? m_marginTop + height() + m_marginBottom : m_marginRight + width() + m_marginLeft;
+        if (baselineType == AlphabeticBaseline)
+            return result;
+        return result - result / 2;
+    }
+    return 0;
+}
+
+
+RenderLayer* RenderBox::enclosingFloatPaintingLayer() const
+{
+    const RenderObject* curr = this;
+    while (curr) {
+        RenderLayer* layer = curr->hasLayer() && curr->isBox() ? toRenderBoxModelObject(curr)->layer() : 0;
+        if (layer && layer->isSelfPaintingLayer())
+            return layer;
+        curr = curr->parent();
+    }
+    return 0;
+}
+
+IntRect RenderBox::logicalVisualOverflowRectForPropagation(RenderStyle* parentStyle) const
+{
+    IntRect rect = visualOverflowRectForPropagation(parentStyle);
+    if (!parentStyle->isHorizontalWritingMode())
+        return rect.transposedRect();
+    return rect;
+}
+
+IntRect RenderBox::visualOverflowRectForPropagation(RenderStyle* parentStyle) const
+{
+    // If the writing modes of the child and parent match, then we don't have to 
+    // do anything fancy. Just return the result.
+    IntRect rect = visualOverflowRect();
+    if (parentStyle->writingMode() == style()->writingMode())
+        return rect;
+    
+    // We are putting ourselves into our parent's coordinate space.  If there is a flipped block mismatch
+    // in a particular axis, then we have to flip the rect along that axis.
+    if (style()->writingMode() == RightToLeftWritingMode || parentStyle->writingMode() == RightToLeftWritingMode)
+        rect.setX(width() - rect.right());
+    else if (style()->writingMode() == BottomToTopWritingMode || parentStyle->writingMode() == BottomToTopWritingMode)
+        rect.setY(height() - rect.bottom());
+
+    return rect;
+}
+
+IntRect RenderBox::logicalLayoutOverflowRectForPropagation(RenderStyle* parentStyle) const
+{
+    IntRect rect = layoutOverflowRectForPropagation(parentStyle);
+    if (!parentStyle->isHorizontalWritingMode())
+        return rect.transposedRect();
+    return rect;
+}
+
+IntRect RenderBox::layoutOverflowRectForPropagation(RenderStyle* parentStyle) const
+{
+    // Only propagate interior layout overflow if we don't clip it.
+    IntRect rect = borderBoxRect();
+    if (!hasOverflowClip())
+        rect.unite(layoutOverflowRect());
+
+    if (isRelPositioned() || hasTransform()) {
+        // If we are relatively positioned or if we have a transform, then we have to convert
+        // this rectangle into physical coordinates, apply relative positioning and transforms
+        // to it, and then convert it back.
+        flipForWritingMode(rect);
+        
+        if (hasTransform())
+            rect = layer()->currentTransform().mapRect(rect);
+
+        if (isRelPositioned())
+            rect.move(relativePositionOffsetX(), relativePositionOffsetY());
+        
+        // Now we need to flip back.
+        flipForWritingMode(rect);
+    }
+    
+    // If the writing modes of the child and parent match, then we don't have to 
+    // do anything fancy. Just return the result.
+    if (parentStyle->writingMode() == style()->writingMode())
+        return rect;
+    
+    // We are putting ourselves into our parent's coordinate space.  If there is a flipped block mismatch
+    // in a particular axis, then we have to flip the rect along that axis.
+    if (style()->writingMode() == RightToLeftWritingMode || parentStyle->writingMode() == RightToLeftWritingMode)
+        rect.setX(width() - rect.right());
+    else if (style()->writingMode() == BottomToTopWritingMode || parentStyle->writingMode() == BottomToTopWritingMode)
+        rect.setY(height() - rect.bottom());
+
+    return rect;
+}
+
+IntPoint RenderBox::flipForWritingMode(const RenderBox* child, const IntPoint& point, FlippingAdjustment adjustment) const
+{
+    if (!style()->isFlippedBlocksWritingMode())
+        return point;
+    
+    // The child is going to add in its x() and y(), so we have to make sure it ends up in
+    // the right place.
+    if (style()->isHorizontalWritingMode())
+        return IntPoint(point.x(), point.y() + height() - child->height() - child->y() - (adjustment == ParentToChildFlippingAdjustment ? child->y() : 0));
+    return IntPoint(point.x() + width() - child->width() - child->x() - (adjustment == ParentToChildFlippingAdjustment ? child->x() : 0), point.y());
+}
+
+void RenderBox::flipForWritingMode(IntRect& rect) const
+{
+    if (!style()->isFlippedBlocksWritingMode())
+        return;
+
+    if (style()->isHorizontalWritingMode())
+        rect.setY(height() - rect.bottom());
+    else
+        rect.setX(width() - rect.right());
+}
+
+int RenderBox::flipForWritingMode(int position) const
+{
+    if (!style()->isFlippedBlocksWritingMode())
+        return position;
+    return logicalHeight() - position;
+}
+
+IntPoint RenderBox::flipForWritingMode(const IntPoint& position) const
+{
+    if (!style()->isFlippedBlocksWritingMode())
+        return position;
+    return style()->isHorizontalWritingMode() ? IntPoint(position.x(), height() - position.y()) : IntPoint(width() - position.x(), position.y());
+}
+
+IntSize RenderBox::flipForWritingMode(const IntSize& offset) const
+{
+    if (!style()->isFlippedBlocksWritingMode())
+        return offset;
+    return style()->isHorizontalWritingMode() ? IntSize(offset.width(), height() - offset.height()) : IntSize(width() - offset.width(), offset.height());
+}
+
+IntSize RenderBox::locationOffsetIncludingFlipping() const
+{
+    if (!parent() || !parent()->isBox())
+        return locationOffset();
+    
+    IntRect rect(frameRect());
+    parentBox()->flipForWritingMode(rect);
+    return IntSize(rect.x(), rect.y());
+}
+
+} // namespace WebCore