Merge WebKit r47420

1 files changed, 33 insertions, 28 deletions

diff --git a/WebCore/rendering/RenderBox.cpp b/WebCore/rendering/RenderBox.cpp
index 4c2bff0..a1a2d9a 100644
--- a/WebCore/rendering/RenderBox.cpp
+++ b/WebCore/rendering/RenderBox.cpp
@@ -416,6 +416,11 @@ bool RenderBox::scroll(ScrollDirection direction, ScrollGranularity granularity,
         return b->scroll(direction, granularity, multiplier);
     return false;
 }
+
+bool RenderBox::canBeScrolledAndHasScrollableArea() const
+{
+   return canBeProgramaticallyScrolled(false) && (scrollHeight() != clientHeight() || scrollWidth() != clientWidth());
+}
     
 bool RenderBox::canBeProgramaticallyScrolled(bool) const
 {
@@ -653,31 +658,36 @@ void RenderBox::paintMaskImages(const PaintInfo& paintInfo, int tx, int ty, int
 {
     // Figure out if we need to push a transparency layer to render our mask.
     bool pushTransparencyLayer = false;
-    StyleImage* maskBoxImage = style()->maskBoxImage().image();
-    if (maskBoxImage && style()->maskLayers()->hasImage()) {
-        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 = style()->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;
+    bool compositedMask = hasLayer() && layer()->hasCompositedMask();
+    CompositeOperator compositeOp = CompositeSourceOver;
+
+    if (!compositedMask) {
+        StyleImage* maskBoxImage = style()->maskBoxImage().image();
+        if (maskBoxImage && style()->maskLayers()->hasImage()) {
+            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 = style()->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;
+                }
             }
         }
-    }
-    
-    CompositeOperator compositeOp = CompositeDestinationIn;
-    if (pushTransparencyLayer) {
-        paintInfo.context->setCompositeOperation(CompositeDestinationIn);
-        paintInfo.context->beginTransparencyLayer(1.0f);
-        compositeOp = CompositeSourceOver;
+        
+        compositeOp = CompositeDestinationIn;
+        if (pushTransparencyLayer) {
+            paintInfo.context->setCompositeOperation(CompositeDestinationIn);
+            paintInfo.context->beginTransparencyLayer(1.0f);
+            compositeOp = CompositeSourceOver;
+        }
     }
 
     paintFillLayers(paintInfo, Color(), style()->maskLayers(), tx, ty, w, h, compositeOp);
@@ -2701,11 +2711,6 @@ int RenderBox::leftmostPosition(bool /*includeOverflowInterior*/, bool includeSe
     return left;
 }
 
-bool RenderBox::isAfterContent(RenderObject* child) const
-{
-    return (child && child->style()->styleType() == AFTER && (!child->isText() || child->isBR()));
-}
-
 VisiblePosition RenderBox::positionForPoint(const IntPoint& point)
 {
     // no children...return this render object's element, if there is one, and offset 0