Merge WebKit at r80534: Intial merge by Git

Change-Id: Ia7a83357124c9e1cdb1debf55d9661ec0bd09a61

28 files changed, 493 insertions, 843 deletions

diff --git a/Source/WebKit2/WebProcess/WebPage/ChunkedUpdateDrawingArea.cpp b/Source/WebKit2/WebProcess/WebPage/ChunkedUpdateDrawingArea.cpp
index f5100aa..ed40063 100644
--- a/Source/WebKit2/WebProcess/WebPage/ChunkedUpdateDrawingArea.cpp
+++ b/Source/WebKit2/WebProcess/WebPage/ChunkedUpdateDrawingArea.cpp
@@ -38,8 +38,8 @@ using namespace WebCore;
 
 namespace WebKit {
 
-ChunkedUpdateDrawingArea::ChunkedUpdateDrawingArea(DrawingAreaInfo::Identifier identifier, WebPage* webPage)
-    : DrawingArea(DrawingAreaInfo::ChunkedUpdate, identifier, webPage)
+ChunkedUpdateDrawingArea::ChunkedUpdateDrawingArea(WebPage* webPage)
+    : DrawingArea(DrawingAreaTypeChunkedUpdate, webPage)
     , m_isWaitingForUpdate(false)
     , m_paintingIsSuspended(false)
     , m_displayTimer(WebProcess::shared().runLoop(), this, &ChunkedUpdateDrawingArea::display)
@@ -74,15 +74,9 @@ void ChunkedUpdateDrawingArea::display()
     if (m_dirtyRect.isEmpty())
         return;
 
-    // Laying out the page can cause the drawing area to change so we keep an extra reference.
-    RefPtr<ChunkedUpdateDrawingArea> protect(this);
-
     // Layout if necessary.
     m_webPage->layoutIfNeeded();
  
-    if (m_webPage->drawingArea() != this)
-        return;
-    
     IntRect dirtyRect = m_dirtyRect;
     m_dirtyRect = IntRect();
 
@@ -126,15 +120,9 @@ void ChunkedUpdateDrawingArea::setSize(const IntSize& viewSize)
     // We don't want to wait for an update until we display.
     m_isWaitingForUpdate = false;
     
-    // Laying out the page can cause the drawing area to change so we keep an extra reference.
-    RefPtr<ChunkedUpdateDrawingArea> protect(this);
-
     m_webPage->setSize(viewSize);
     m_webPage->layoutIfNeeded();
 
-    if (m_webPage->drawingArea() != this)
-        return;
-
     if (m_paintingIsSuspended) {
         ASSERT(!m_displayTimer.isActive());
 
@@ -160,7 +148,7 @@ void ChunkedUpdateDrawingArea::suspendPainting()
     m_displayTimer.stop();
 }
 
-void ChunkedUpdateDrawingArea::resumePainting(bool forceRepaint)
+void ChunkedUpdateDrawingArea::deprecatedResumePainting(bool forceRepaint)
 {
     ASSERT(m_paintingIsSuspended);
     
@@ -185,14 +173,6 @@ void ChunkedUpdateDrawingArea::didUpdate()
 
 void ChunkedUpdateDrawingArea::didReceiveMessage(CoreIPC::Connection*, CoreIPC::MessageID messageID, CoreIPC::ArgumentDecoder* arguments)
 {
-    DrawingAreaInfo::Identifier targetIdentifier;
-    if (!arguments->decode(CoreIPC::Out(targetIdentifier)))
-        return;
-
-    // We can switch drawing areas on the fly, so if this message was targetted at an obsolete drawing area, ignore it.
-    if (targetIdentifier != info().identifier)
-        return;
-
     switch (messageID.get<DrawingAreaLegacyMessage::Kind>()) {
         case DrawingAreaLegacyMessage::SetSize: {
             IntSize size;
@@ -212,7 +192,7 @@ void ChunkedUpdateDrawingArea::didReceiveMessage(CoreIPC::Connection*, CoreIPC::
             if (!arguments->decode(CoreIPC::Out(forceRepaint)))
                 return;
             
-            resumePainting(forceRepaint);
+            deprecatedResumePainting(forceRepaint);
             break;
         }
         case DrawingAreaLegacyMessage::DidUpdate:
diff --git a/Source/WebKit2/WebProcess/WebPage/ChunkedUpdateDrawingArea.h b/Source/WebKit2/WebProcess/WebPage/ChunkedUpdateDrawingArea.h
index d32ed4c..5798ef6 100644
--- a/Source/WebKit2/WebProcess/WebPage/ChunkedUpdateDrawingArea.h
+++ b/Source/WebKit2/WebProcess/WebPage/ChunkedUpdateDrawingArea.h
@@ -36,7 +36,7 @@ class UpdateChunk;
 
 class ChunkedUpdateDrawingArea : public DrawingArea {
 public:
-    ChunkedUpdateDrawingArea(DrawingAreaInfo::Identifier identifier, WebPage*);
+    explicit ChunkedUpdateDrawingArea(WebPage*);
     virtual ~ChunkedUpdateDrawingArea();
 
     virtual void setNeedsDisplay(const WebCore::IntRect&);
@@ -45,8 +45,6 @@ public:
     virtual void forceRepaint();
 
 #if USE(ACCELERATED_COMPOSITING)
-    virtual void attachCompositingContext() { }
-    virtual void detachCompositingContext() { }
     virtual void setRootCompositingLayer(WebCore::GraphicsLayer*) { }
     virtual void scheduleCompositingLayerSync() { }
     virtual void syncCompositingLayers() { }
@@ -60,7 +58,7 @@ private:
     // CoreIPC message handlers.
     void setSize(const WebCore::IntSize& viewSize);
     void suspendPainting();
-    void resumePainting(bool forceRepaint);
+    void deprecatedResumePainting(bool forceRepaint);
     void didUpdate();
 
     // Platform overrides
diff --git a/Source/WebKit2/WebProcess/WebPage/DrawingArea.cpp b/Source/WebKit2/WebProcess/WebPage/DrawingArea.cpp
index 10a8dbf..c808b19 100644
--- a/Source/WebKit2/WebProcess/WebPage/DrawingArea.cpp
+++ b/Source/WebKit2/WebProcess/WebPage/DrawingArea.cpp
@@ -33,10 +33,6 @@
 #include "DrawingAreaImpl.h"
 #endif
 
-#if USE(ACCELERATED_COMPOSITING)
-#include "LayerBackedDrawingArea.h"
-#endif
-
 #if ENABLE(TILED_BACKING_STORE)
 #include "TiledDrawingArea.h"
 #endif
@@ -45,37 +41,29 @@
 
 namespace WebKit {
 
-PassRefPtr<DrawingArea> DrawingArea::create(WebPage* webPage, const WebPageCreationParameters& parameters)
+PassOwnPtr<DrawingArea> DrawingArea::create(WebPage* webPage, const WebPageCreationParameters& parameters)
 {
-    switch (parameters.drawingAreaInfo.type) {
-        case DrawingAreaInfo::None:
-            ASSERT_NOT_REACHED();
-            break;
-
-        case DrawingAreaInfo::Impl:
+    switch (parameters.drawingAreaType) {
+    case DrawingAreaTypeImpl:
 #if PLATFORM(MAC) || PLATFORM(WIN)
-            return DrawingAreaImpl::create(webPage, parameters);
+        return DrawingAreaImpl::create(webPage, parameters);
 #else
-            return 0;
+        return 0;
 #endif
-        case DrawingAreaInfo::ChunkedUpdate:
-            return adoptRef(new ChunkedUpdateDrawingArea(parameters.drawingAreaInfo.identifier, webPage));
+    case DrawingAreaTypeChunkedUpdate:
+        return adoptPtr(new ChunkedUpdateDrawingArea(webPage));
 
-#if USE(ACCELERATED_COMPOSITING) && PLATFORM(MAC)
-        case DrawingAreaInfo::LayerBacked:
-            return adoptRef(new LayerBackedDrawingArea(parameters.drawingAreaInfo.identifier, webPage));
-#endif
 #if ENABLE(TILED_BACKING_STORE)
-        case DrawingAreaInfo::Tiled:
-            return adoptRef(new TiledDrawingArea(parameters.drawingAreaInfo.identifier, webPage));
+    case DrawingAreaTypeTiled:
+        return adoptPtr(new TiledDrawingArea(webPage));
 #endif
     }
 
     return 0;
 }
 
-DrawingArea::DrawingArea(DrawingAreaInfo::Type type, DrawingAreaInfo::Identifier identifier, WebPage* webPage)
-    : m_info(type, identifier)
+DrawingArea::DrawingArea(DrawingAreaType type, WebPage* webPage)
+    : m_type(type)
     , m_webPage(webPage)
 {
 }
diff --git a/Source/WebKit2/WebProcess/WebPage/DrawingArea.h b/Source/WebKit2/WebProcess/WebPage/DrawingArea.h
index de256b6..940e40e 100644
--- a/Source/WebKit2/WebProcess/WebPage/DrawingArea.h
+++ b/Source/WebKit2/WebProcess/WebPage/DrawingArea.h
@@ -28,13 +28,17 @@
 
 #include "DrawingAreaInfo.h"
 #include <WebCore/IntRect.h>
-#include <wtf/PassRefPtr.h>
-#include <wtf/RefCounted.h>
+#include <wtf/Noncopyable.h>
+#include <wtf/PassOwnPtr.h>
+
+namespace CoreIPC {
+    class ArgumentDecoder;
+    class Connection;
+    class MessageID;
+}
 
 namespace WebCore {
-#if USE(ACCELERATED_COMPOSITING)
     class GraphicsLayer;
-#endif
 }
 
 namespace WebKit {
@@ -42,10 +46,11 @@ namespace WebKit {
 class WebPage;
 struct WebPageCreationParameters;
 
-class DrawingArea : public RefCounted<DrawingArea> {
+class DrawingArea {
+    WTF_MAKE_NONCOPYABLE(DrawingArea);
+
 public:
-    // FIXME: It might make sense to move this create function into a factory style class. 
-    static PassRefPtr<DrawingArea> create(WebPage*, const WebPageCreationParameters&);
+    static PassOwnPtr<DrawingArea> create(WebPage*, const WebPageCreationParameters&);
     virtual ~DrawingArea();
     
 #if PLATFORM(MAC) || PLATFORM(WIN)
@@ -57,7 +62,6 @@ public:
 
     // FIXME: These should be pure virtual.
     virtual void pageBackgroundTransparencyChanged() { }
-    virtual void onPageClose() { }
     virtual void forceRepaint() { }
 
     virtual void didInstallPageOverlay() { }
@@ -65,8 +69,6 @@ public:
     virtual void setPageOverlayNeedsDisplay(const WebCore::IntRect&) { }
 
 #if USE(ACCELERATED_COMPOSITING)
-    virtual void attachCompositingContext() = 0;
-    virtual void detachCompositingContext() = 0;
     virtual void setRootCompositingLayer(WebCore::GraphicsLayer*) = 0;
     virtual void scheduleCompositingLayerSync() = 0;
     virtual void syncCompositingLayers() = 0;
@@ -74,18 +76,16 @@ public:
 
     virtual void didReceiveMessage(CoreIPC::Connection*, CoreIPC::MessageID, CoreIPC::ArgumentDecoder*) = 0;
 
-    const DrawingAreaInfo& info() const { return m_info; }
-
 protected:
-    DrawingArea(DrawingAreaInfo::Type, DrawingAreaInfo::Identifier, WebPage*);
+    DrawingArea(DrawingAreaType, WebPage*);
 
-    DrawingAreaInfo m_info;
+    DrawingAreaType m_type;
     WebPage* m_webPage;
 
 private:
     // CoreIPC message handlers.
     // FIXME: These should be pure virtual.
-    virtual void setSize(const WebCore::IntSize& size, const WebCore::IntSize& scrollOffset) { }
+    virtual void updateBackingStoreState(uint64_t backingStoreStateID, bool respondImmediately, const WebCore::IntSize& size, const WebCore::IntSize& scrollOffset) { }
     virtual void didUpdate() { }
     virtual void suspendPainting() { }
     virtual void resumePainting() { }
diff --git a/Source/WebKit2/WebProcess/WebPage/DrawingArea.messages.in b/Source/WebKit2/WebProcess/WebPage/DrawingArea.messages.in
index ec09e18..30186f2 100644
--- a/Source/WebKit2/WebProcess/WebPage/DrawingArea.messages.in
+++ b/Source/WebKit2/WebProcess/WebPage/DrawingArea.messages.in
@@ -21,7 +21,7 @@
 # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 messages -> DrawingArea {
-    SetSize(WebCore::IntSize size, WebCore::IntSize scrollOffset)
+    UpdateBackingStoreState(uint64_t backingStoreStateID, bool respondImmediately, WebCore::IntSize size, WebCore::IntSize scrollOffset)
     DidUpdate()
     SuspendPainting()
     ResumePainting()
diff --git a/Source/WebKit2/WebProcess/WebPage/DrawingAreaImpl.cpp b/Source/WebKit2/WebProcess/WebPage/DrawingAreaImpl.cpp
index 6d65fae..0a18256 100644
--- a/Source/WebKit2/WebProcess/WebPage/DrawingAreaImpl.cpp
+++ b/Source/WebKit2/WebProcess/WebPage/DrawingAreaImpl.cpp
@@ -34,6 +34,8 @@
 #include "WebPageCreationParameters.h"
 #include "WebProcess.h"
 #include <WebCore/GraphicsContext.h>
+#include <WebCore/Page.h>
+#include <WebCore/Settings.h>
 
 #if !PLATFORM(MAC) && !PLATFORM(WIN)
 #error "This drawing area is not ready for use by other ports yet."
@@ -43,15 +45,9 @@ using namespace WebCore;
 
 namespace WebKit {
 
-static uint64_t generateSequenceNumber()
+PassOwnPtr<DrawingAreaImpl> DrawingAreaImpl::create(WebPage* webPage, const WebPageCreationParameters& parameters)
 {
-    static uint64_t sequenceNumber;
-    return ++sequenceNumber;
-}
-
-PassRefPtr<DrawingAreaImpl> DrawingAreaImpl::create(WebPage* webPage, const WebPageCreationParameters& parameters)
-{
-    return adoptRef(new DrawingAreaImpl(webPage, parameters));
+    return adoptPtr(new DrawingAreaImpl(webPage, parameters));
 }
 
 DrawingAreaImpl::~DrawingAreaImpl()
@@ -61,13 +57,21 @@ DrawingAreaImpl::~DrawingAreaImpl()
 }
 
 DrawingAreaImpl::DrawingAreaImpl(WebPage* webPage, const WebPageCreationParameters& parameters)
-    : DrawingArea(DrawingAreaInfo::Impl, parameters.drawingAreaInfo.identifier, webPage)
-    , m_inSetSize(false)
+    : DrawingArea(DrawingAreaTypeImpl, webPage)
+    , m_backingStoreStateID(0)
+    , m_inUpdateBackingStoreState(false)
+    , m_shouldSendDidUpdateBackingStoreState(false)
     , m_isWaitingForDidUpdate(false)
     , m_isPaintingSuspended(!parameters.isVisible)
+    , m_alwaysUseCompositing(false)
     , m_displayTimer(WebProcess::shared().runLoop(), this, &DrawingAreaImpl::display)
     , m_exitCompositingTimer(WebProcess::shared().runLoop(), this, &DrawingAreaImpl::exitAcceleratedCompositingMode)
 {
+    if (webPage->corePage()->settings()->acceleratedDrawingEnabled())
+        m_alwaysUseCompositing = true;
+        
+    if (m_alwaysUseCompositing)
+        enterAcceleratedCompositingMode(0);
 }
 
 void DrawingAreaImpl::setNeedsDisplay(const IntRect& rect)
@@ -142,6 +146,15 @@ void DrawingAreaImpl::scroll(const IntRect& scrollRect, const IntSize& scrollOff
 
 void DrawingAreaImpl::forceRepaint()
 {
+    setNeedsDisplay(m_webPage->bounds());
+
+    m_webPage->layoutIfNeeded();
+
+    if (m_layerTreeHost) {
+        m_layerTreeHost->forceRepaint();
+        return;
+    }
+
     m_isWaitingForDidUpdate = false;
     display();
 }
@@ -170,12 +183,21 @@ void DrawingAreaImpl::setPageOverlayNeedsDisplay(const IntRect& rect)
     setNeedsDisplay(rect);
 }
 
-void DrawingAreaImpl::attachCompositingContext()
+void DrawingAreaImpl::layerHostDidFlushLayers()
 {
-}
+    ASSERT(m_layerTreeHost);
 
-void DrawingAreaImpl::detachCompositingContext()
-{
+    m_layerTreeHost->forceRepaint();
+
+    if (m_shouldSendDidUpdateBackingStoreState) {
+        sendDidUpdateBackingStoreState();
+        return;
+    }
+
+    if (!m_layerTreeHost)
+        return;
+
+    m_webPage->send(Messages::DrawingAreaProxy::EnterAcceleratedCompositingMode(m_backingStoreStateID, m_layerTreeHost->layerTreeContext()));
 }
 
 void DrawingAreaImpl::setRootCompositingLayer(GraphicsLayer* graphicsLayer)
@@ -191,9 +213,17 @@ void DrawingAreaImpl::setRootCompositingLayer(GraphicsLayer* graphicsLayer)
         }
     } else {
         if (m_layerTreeHost) {
-            // We'll exit accelerated compositing mode on a timer, to avoid re-entering
-            // compositing code via display() and layout.
-            exitAcceleratedCompositingModeSoon();
+            m_layerTreeHost->setRootCompositingLayer(0);
+            if (!m_alwaysUseCompositing) {
+                // We'll exit accelerated compositing mode on a timer, to avoid re-entering
+                // compositing code via display() and layout.
+                // If we're leaving compositing mode because of a setSize, it is safe to
+                // exit accelerated compositing mode right away.
+                if (m_inUpdateBackingStoreState)
+                    exitAcceleratedCompositingMode();
+                else
+                    exitAcceleratedCompositingModeSoon();
+            }
         }
     }
 }
@@ -213,39 +243,74 @@ void DrawingAreaImpl::didReceiveMessage(CoreIPC::Connection*, CoreIPC::MessageID
 {
 }
 
-void DrawingAreaImpl::setSize(const WebCore::IntSize& size, const WebCore::IntSize& scrollOffset)
+void DrawingAreaImpl::updateBackingStoreState(uint64_t stateID, bool respondImmediately, const WebCore::IntSize& size, const WebCore::IntSize& scrollOffset)
 {
-    ASSERT(!m_inSetSize);
-    m_inSetSize = true;
+    ASSERT(!m_inUpdateBackingStoreState);
+    m_inUpdateBackingStoreState = true;
+
+    ASSERT_ARG(stateID, stateID >= m_backingStoreStateID);
+    if (stateID != m_backingStoreStateID) {
+        m_backingStoreStateID = stateID;
+        m_shouldSendDidUpdateBackingStoreState = true;
+
+        m_webPage->setSize(size);
+        m_webPage->layoutIfNeeded();
+        m_webPage->scrollMainFrameIfNotAtMaxScrollPosition(scrollOffset);
+
+        if (m_layerTreeHost)
+            m_layerTreeHost->sizeDidChange(size);
+        else
+            m_dirtyRegion = m_webPage->bounds();
+    } else {
+        ASSERT(size == m_webPage->size());
+        if (!m_shouldSendDidUpdateBackingStoreState) {
+            // We've already sent a DidUpdateBackingStoreState message for this state. We have nothing more to do.
+            m_inUpdateBackingStoreState = false;
+            return;
+        }
+    }
 
-    // Set this to false since we're about to call display().
+    // The UI process has updated to a new backing store state. Any Update messages we sent before
+    // this point will be ignored. We wait to set this to false until after updating the page's
+    // size so that any displays triggered by the relayout will be ignored. If we're supposed to
+    // respond to the UpdateBackingStoreState message immediately, we'll do a display anyway in
+    // sendDidUpdateBackingStoreState; otherwise we shouldn't do one right now.
     m_isWaitingForDidUpdate = false;
 
-    m_webPage->setSize(size);
-    m_webPage->layoutIfNeeded();
-    m_webPage->scrollMainFrameIfNotAtMaxScrollPosition(scrollOffset);
+    if (respondImmediately)
+        sendDidUpdateBackingStoreState();
+
+    m_inUpdateBackingStoreState = false;
+}
+
+void DrawingAreaImpl::sendDidUpdateBackingStoreState()
+{
+    ASSERT(!m_isWaitingForDidUpdate);
+    ASSERT(m_shouldSendDidUpdateBackingStoreState);
+
+    m_shouldSendDidUpdateBackingStoreState = false;
 
     UpdateInfo updateInfo;
     LayerTreeContext layerTreeContext;
 
-    if (m_layerTreeHost) {
-        m_layerTreeHost->sizeDidChange(size);
-        layerTreeContext = m_layerTreeHost->layerTreeContext();
-    }
+    if (!m_isPaintingSuspended && !m_layerTreeHost)
+        display(updateInfo);
 
-    if (m_isPaintingSuspended || m_layerTreeHost)
+    if (m_isPaintingSuspended || m_layerTreeHost) {
         updateInfo.viewSize = m_webPage->size();
-    else {
-        m_dirtyRegion.unite(m_webPage->bounds());
 
-        // The display here should not cause layout to happen, so we can't enter accelerated compositing mode here.
-        display(updateInfo);
-        ASSERT(!m_layerTreeHost);
-    }
+        if (m_layerTreeHost) {
+            layerTreeContext = m_layerTreeHost->layerTreeContext();
 
-    m_webPage->send(Messages::DrawingAreaProxy::DidSetSize(generateSequenceNumber(), updateInfo, layerTreeContext));
+            // We don't want the layer tree host to notify after the next scheduled
+            // layer flush because that might end up sending an EnterAcceleratedCompositingMode
+            // message back to the UI process, but the updated layer tree context
+            // will be sent back in the DidUpdateBackingStoreState message.
+            m_layerTreeHost->setShouldNotifyAfterNextScheduledLayerFlush(false);
+        }
+    }
 
-    m_inSetSize = false;
+    m_webPage->send(Messages::DrawingAreaProxy::DidUpdateBackingStoreState(m_backingStoreStateID, updateInfo, layerTreeContext));
 }
 
 void DrawingAreaImpl::didUpdate()
@@ -286,6 +351,9 @@ void DrawingAreaImpl::enterAcceleratedCompositingMode(GraphicsLayer* graphicsLay
     ASSERT(!m_layerTreeHost);
 
     m_layerTreeHost = LayerTreeHost::create(m_webPage);
+    if (!m_inUpdateBackingStoreState)
+        m_layerTreeHost->setShouldNotifyAfterNextScheduledLayerFlush(true);
+
     m_layerTreeHost->setRootCompositingLayer(graphicsLayer);
     
     // Non-composited content will now be handled exclusively by the layer tree host.
@@ -294,35 +362,38 @@ void DrawingAreaImpl::enterAcceleratedCompositingMode(GraphicsLayer* graphicsLay
     m_scrollOffset = IntSize();
     m_displayTimer.stop();
     m_isWaitingForDidUpdate = false;
-
-    if (!m_inSetSize)
-        m_webPage->send(Messages::DrawingAreaProxy::EnterAcceleratedCompositingMode(generateSequenceNumber(), m_layerTreeHost->layerTreeContext()));
 }
 
 void DrawingAreaImpl::exitAcceleratedCompositingMode()
 {
+    if (m_alwaysUseCompositing)
+        return;
+
     m_exitCompositingTimer.stop();
 
     ASSERT(m_layerTreeHost);
 
     m_layerTreeHost->invalidate();
     m_layerTreeHost = nullptr;
+    m_dirtyRegion = m_webPage->bounds();
+
+    if (m_inUpdateBackingStoreState)
+        return;
 
-    if (m_inSetSize)
+    if (m_shouldSendDidUpdateBackingStoreState) {
+        sendDidUpdateBackingStoreState();
         return;
+    }
 
     UpdateInfo updateInfo;
     if (m_isPaintingSuspended)
         updateInfo.viewSize = m_webPage->size();
-    else {
-        m_dirtyRegion = m_webPage->bounds();
+    else
         display(updateInfo);
-    }
 
     // Send along a complete update of the page so we can paint the contents right after we exit the
     // accelerated compositing mode, eliminiating flicker.
-    if (!m_inSetSize)
-        m_webPage->send(Messages::DrawingAreaProxy::ExitAcceleratedCompositingMode(generateSequenceNumber(), updateInfo));
+    m_webPage->send(Messages::DrawingAreaProxy::ExitAcceleratedCompositingMode(m_backingStoreStateID, updateInfo));
 }
 
 void DrawingAreaImpl::exitAcceleratedCompositingModeSoon()
@@ -354,6 +425,7 @@ void DrawingAreaImpl::display()
 {
     ASSERT(!m_layerTreeHost);
     ASSERT(!m_isWaitingForDidUpdate);
+    ASSERT(!m_inUpdateBackingStoreState);
 
     if (m_isPaintingSuspended)
         return;
@@ -361,6 +433,11 @@ void DrawingAreaImpl::display()
     if (m_dirtyRegion.isEmpty())
         return;
 
+    if (m_shouldSendDidUpdateBackingStoreState) {
+        sendDidUpdateBackingStoreState();
+        return;
+    }
+
     UpdateInfo updateInfo;
     display(updateInfo);
 
@@ -370,7 +447,7 @@ void DrawingAreaImpl::display()
         return;
     }
 
-    m_webPage->send(Messages::DrawingAreaProxy::Update(generateSequenceNumber(), updateInfo));
+    m_webPage->send(Messages::DrawingAreaProxy::Update(m_backingStoreStateID, updateInfo));
     m_isWaitingForDidUpdate = true;
 }
 
@@ -405,7 +482,20 @@ void DrawingAreaImpl::display(UpdateInfo& updateInfo)
     if (m_webPage->mainFrameHasCustomRepresentation())
         return;
 
+    m_webPage->layoutIfNeeded();
+
+    // The layout may have put the page into accelerated compositing mode, in which case the
+    // LayerTreeHost is now in charge of displaying.
+    if (m_layerTreeHost)
+        return;
+
     IntRect bounds = m_dirtyRegion.bounds();
+    ASSERT(m_webPage->bounds().contains(bounds));
+
+    RefPtr<ShareableBitmap> bitmap = ShareableBitmap::createShareable(bounds.size());
+    if (!bitmap->createHandle(updateInfo.bitmapHandle))
+        return;
+
     Vector<IntRect> rects = m_dirtyRegion.rects();
 
     if (shouldPaintBoundsRect(bounds, rects)) {
@@ -419,14 +509,8 @@ void DrawingAreaImpl::display(UpdateInfo& updateInfo)
     m_dirtyRegion = Region();
     m_scrollRect = IntRect();
     m_scrollOffset = IntSize();
-    
-    RefPtr<ShareableBitmap> bitmap = ShareableBitmap::createShareable(bounds.size());
-    if (!bitmap->createHandle(updateInfo.bitmapHandle))
-        return;
 
     OwnPtr<GraphicsContext> graphicsContext = bitmap->createGraphicsContext();
-
-    m_webPage->layoutIfNeeded();
     
     updateInfo.viewSize = m_webPage->size();
     updateInfo.updateRectBounds = bounds;
diff --git a/Source/WebKit2/WebProcess/WebPage/DrawingAreaImpl.h b/Source/WebKit2/WebProcess/WebPage/DrawingAreaImpl.h
index cbb94c2..8d85200 100644
--- a/Source/WebKit2/WebProcess/WebPage/DrawingAreaImpl.h
+++ b/Source/WebKit2/WebProcess/WebPage/DrawingAreaImpl.h
@@ -37,9 +37,11 @@ class UpdateInfo;
 
 class DrawingAreaImpl : public DrawingArea {
 public:
-    static PassRefPtr<DrawingAreaImpl> create(WebPage*, const WebPageCreationParameters&);
+    static PassOwnPtr<DrawingAreaImpl> create(WebPage*, const WebPageCreationParameters&);
     virtual ~DrawingAreaImpl();
 
+    void layerHostDidFlushLayers();
+
 private:
     DrawingAreaImpl(WebPage*, const WebPageCreationParameters&);
 
@@ -52,19 +54,19 @@ private:
     virtual void didUninstallPageOverlay();
     virtual void setPageOverlayNeedsDisplay(const WebCore::IntRect&);
     
-    virtual void attachCompositingContext();
-    virtual void detachCompositingContext();
     virtual void setRootCompositingLayer(WebCore::GraphicsLayer*);
     virtual void scheduleCompositingLayerSync();
     virtual void syncCompositingLayers();
     virtual void didReceiveMessage(CoreIPC::Connection*, CoreIPC::MessageID, CoreIPC::ArgumentDecoder*);
 
     // CoreIPC message handlers.
-    virtual void setSize(const WebCore::IntSize&, const WebCore::IntSize& scrollOffset);
+    virtual void updateBackingStoreState(uint64_t backingStoreStateID, bool respondImmediately, const WebCore::IntSize&, const WebCore::IntSize& scrollOffset);
     virtual void didUpdate();
     virtual void suspendPainting();
     virtual void resumePainting();
 
+    void sendDidUpdateBackingStoreState();
+
     void enterAcceleratedCompositingMode(WebCore::GraphicsLayer*);
     void exitAcceleratedCompositingModeSoon();
     void exitAcceleratedCompositingMode();
@@ -73,12 +75,18 @@ private:
     void display();
     void display(UpdateInfo&);
 
+    uint64_t m_backingStoreStateID;
+
     Region m_dirtyRegion;
     WebCore::IntRect m_scrollRect;
     WebCore::IntSize m_scrollOffset;
 
-    // Whether we're currently processing a setSize message.
-    bool m_inSetSize;
+    // Whether we're currently processing an UpdateBackingStoreState message.
+    bool m_inUpdateBackingStoreState;
+
+    // When true, we should send an UpdateBackingStoreState message instead of any other messages
+    // we normally send to the UI process.
+    bool m_shouldSendDidUpdateBackingStoreState;
 
     // Whether we're waiting for a DidUpdate message. Used for throttling paints so that the 
     // web process won't paint more frequent than the UI process can handle.
@@ -87,6 +95,7 @@ private:
     // Whether painting is suspended. We'll still keep track of the dirty region but we 
     // won't paint until painting has resumed again.
     bool m_isPaintingSuspended;
+    bool m_alwaysUseCompositing;
 
     RunLoop::Timer<DrawingAreaImpl> m_displayTimer;
     RunLoop::Timer<DrawingAreaImpl> m_exitCompositingTimer;
diff --git a/Source/WebKit2/WebProcess/WebPage/LayerBackedDrawingArea.cpp b/Source/WebKit2/WebProcess/WebPage/LayerBackedDrawingArea.cpp
deleted file mode 100644
index 44b3bd6..0000000
--- a/Source/WebKit2/WebProcess/WebPage/LayerBackedDrawingArea.cpp
+++ /dev/null
@@ -1,239 +0,0 @@
-/*
- * Copyright (C) 2010 Apple Inc. All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- * 1. Redistributions of source code must retain the above copyright
- *    notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- *    notice, this list of conditions and the following disclaimer in the
- *    documentation and/or other materials provided with the distribution.
- *
- * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
- * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
- * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
- * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
- * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
- * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
- * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
- * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
- * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
- * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
- * THE POSSIBILITY OF SUCH DAMAGE.
- */
-
-#include "config.h"
-#include "LayerBackedDrawingArea.h"
-
-#if USE(ACCELERATED_COMPOSITING)
-
-#include "DrawingAreaMessageKinds.h"
-#include "DrawingAreaProxyMessageKinds.h"
-#include "MessageID.h"
-#include "WebCoreArgumentCoders.h"
-#include "WebPage.h"
-#include "WebProcess.h"
-#include <WebCore/GraphicsLayer.h>
-#include <WebCore/Page.h>
-#include <WebCore/Settings.h>
-
-using namespace WebCore;
-
-namespace WebKit {
-
-LayerBackedDrawingArea::LayerBackedDrawingArea(DrawingAreaInfo::Identifier identifier, WebPage* webPage)
-    : DrawingArea(DrawingAreaInfo::LayerBacked, identifier, webPage)
-    , m_syncTimer(WebProcess::shared().runLoop(), this, &LayerBackedDrawingArea::syncCompositingLayers)
-    , m_attached(false)
-    , m_shouldPaint(true)
-{
-    m_hostingLayer = GraphicsLayer::create(this);
-    m_hostingLayer->setDrawsContent(false);
-#ifndef NDEBUG
-    m_hostingLayer->setName("DrawingArea hosting layer");
-#endif
-    m_hostingLayer->setSize(webPage->size());
-    m_backingLayer = GraphicsLayer::create(this);
-    m_backingLayer->setDrawsContent(true);
-    m_backingLayer->setContentsOpaque(webPage->drawsBackground() && !webPage->drawsTransparentBackground());
-
-#ifndef NDEBUG
-    m_backingLayer->setName("DrawingArea backing layer");
-#endif
-    m_backingLayer->setSize(webPage->size());
-    m_hostingLayer->addChild(m_backingLayer.get());
-    platformInit();
-}
-
-LayerBackedDrawingArea::~LayerBackedDrawingArea()
-{
-    platformClear();
-}
-
-void LayerBackedDrawingArea::scroll(const IntRect& scrollRect, const IntSize& scrollOffset)
-{
-    // FIXME: Do something much smarter.
-    setNeedsDisplay(scrollRect);
-}
-
-void LayerBackedDrawingArea::setNeedsDisplay(const IntRect& rect)
-{
-    m_backingLayer->setNeedsDisplayInRect(rect);
-    scheduleCompositingLayerSync();
-}
-
-void LayerBackedDrawingArea::display()
-{
-    // Laying out the page can cause the drawing area to change so we keep an extra reference.
-    RefPtr<LayerBackedDrawingArea> protect(this);
-
-    // Layout if necessary.
-    m_webPage->layoutIfNeeded();
-
-    if (m_webPage->drawingArea() != this)
-        return;
-}
-
-void LayerBackedDrawingArea::pageBackgroundTransparencyChanged()
-{
-    m_backingLayer->setContentsOpaque(m_webPage->drawsBackground() && !m_webPage->drawsTransparentBackground());
-}
-
-void LayerBackedDrawingArea::scheduleDisplay()
-{
-}
-
-void LayerBackedDrawingArea::setSize(const IntSize& viewSize)
-{
-    ASSERT(m_shouldPaint);
-    ASSERT_ARG(viewSize, !viewSize.isEmpty());
-
-    m_hostingLayer->setSize(viewSize);
-    m_backingLayer->setSize(viewSize);
-    scheduleCompositingLayerSync();
-
-    // Laying out the page can cause the drawing area to change so we keep an extra reference.
-    RefPtr<LayerBackedDrawingArea> protect(this);
-    
-    m_webPage->setSize(viewSize);
-    m_webPage->layoutIfNeeded();
-
-    if (m_webPage->drawingArea() != this)
-        return;
-    
-    WebProcess::shared().connection()->deprecatedSend(DrawingAreaProxyLegacyMessage::DidSetSize, m_webPage->pageID(), CoreIPC::In(viewSize));
-}
-
-void LayerBackedDrawingArea::suspendPainting()
-{
-    ASSERT(m_shouldPaint);
-    
-    m_shouldPaint = false;
-}
-
-void LayerBackedDrawingArea::resumePainting()
-{
-    ASSERT(!m_shouldPaint);
-    
-    m_shouldPaint = true;
-    
-    // Display if needed.
-    display();
-}
-
-void LayerBackedDrawingArea::didUpdate()
-{
-    // Display if needed.
-    display();
-}
-
-void LayerBackedDrawingArea::didReceiveMessage(CoreIPC::Connection*, CoreIPC::MessageID messageID, CoreIPC::ArgumentDecoder* arguments)
-{
-    DrawingAreaInfo::Identifier targetIdentifier;
-    if (!arguments->decode(CoreIPC::Out(targetIdentifier)))
-        return;
-
-    // We can switch drawing areas on the fly, so if this message was targetted at an obsolete drawing area, ignore it.
-    if (targetIdentifier != info().identifier)
-        return;
-
-    switch (messageID.get<DrawingAreaLegacyMessage::Kind>()) {
-        case DrawingAreaLegacyMessage::SetSize: {
-            IntSize size;
-            if (!arguments->decode(CoreIPC::Out(size)))
-                return;
-
-            setSize(size);
-            break;
-        }
-        
-        case DrawingAreaLegacyMessage::SuspendPainting:
-            suspendPainting();
-            break;
-
-        case DrawingAreaLegacyMessage::ResumePainting:
-            resumePainting();
-            break;
-
-        case DrawingAreaLegacyMessage::DidUpdate:
-            didUpdate();
-            break;
-
-        default:
-            ASSERT_NOT_REACHED();
-            break;
-    }
-}
-
-// GraphicsLayerClient methods
-void LayerBackedDrawingArea::paintContents(const GraphicsLayer*, GraphicsContext& graphicsContext, GraphicsLayerPaintingPhase, const IntRect& inClip)
-{
-    m_webPage->drawRect(graphicsContext, inClip);
-}
-
-bool LayerBackedDrawingArea::showDebugBorders() const
-{
-    return m_webPage->corePage()->settings()->showDebugBorders();
-}
-
-bool LayerBackedDrawingArea::showRepaintCounter() const
-{
-    return m_webPage->corePage()->settings()->showRepaintCounter();
-}
-
-#if !PLATFORM(MAC) && !PLATFORM(WIN)
-void LayerBackedDrawingArea::attachCompositingContext(GraphicsLayer*)
-{
-}
-
-void LayerBackedDrawingArea::detachCompositingContext()
-{
-}
-
-#if !PLATFORM(MAC)
-void LayerBackedDrawingArea::setRootCompositingLayer(WebCore::GraphicsLayer*)
-{
-}
-#endif
-
-void LayerBackedDrawingArea::scheduleCompositingLayerSync()
-{
-}
-
-void LayerBackedDrawingArea::syncCompositingLayers()
-{
-}
-
-void LayerBackedDrawingArea::platformInit()
-{
-}
-
-void LayerBackedDrawingArea::platformClear()
-{
-}
-#endif
-
-} // namespace WebKit
-
-#endif // USE(ACCELERATED_COMPOSITING)
diff --git a/Source/WebKit2/WebProcess/WebPage/LayerBackedDrawingArea.h b/Source/WebKit2/WebProcess/WebPage/LayerBackedDrawingArea.h
deleted file mode 100644
index 400c8c5..0000000
--- a/Source/WebKit2/WebProcess/WebPage/LayerBackedDrawingArea.h
+++ /dev/null
@@ -1,123 +0,0 @@
-/*
- * Copyright (C) 2010 Apple Inc. All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- * 1. Redistributions of source code must retain the above copyright
- *    notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- *    notice, this list of conditions and the following disclaimer in the
- *    documentation and/or other materials provided with the distribution.
- *
- * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
- * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
- * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
- * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
- * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
- * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
- * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
- * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
- * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
- * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
- * THE POSSIBILITY OF SUCH DAMAGE.
- */
-
-#ifndef LayerBackedDrawingArea_h
-#define LayerBackedDrawingArea_h
-
-#if USE(ACCELERATED_COMPOSITING)
-
-#include "DrawingArea.h"
-#include "RunLoop.h"
-#include <WebCore/IntPoint.h>
-#include <WebCore/GraphicsLayerClient.h>
-
-#if PLATFORM(MAC)
-#include <wtf/RetainPtr.h>
-OBJC_CLASS NSPopUpButtonCell;
-OBJC_CLASS WKView;
-typedef struct __WKCARemoteLayerClientRef *WKCARemoteLayerClientRef;
-#endif
-
-namespace WebCore {
-    class GraphicsContext;
-    class GraphicsLayer;
-}
-
-namespace WebKit {
-
-class LayerBackedDrawingArea : public DrawingArea, private WebCore::GraphicsLayerClient {
-public:
-    LayerBackedDrawingArea(DrawingAreaInfo::Identifier identifier, WebPage*);
-    virtual ~LayerBackedDrawingArea();
-
-    virtual void setNeedsDisplay(const WebCore::IntRect&);
-    virtual void scroll(const WebCore::IntRect& scrollRect, const WebCore::IntSize& scrollOffset);
-    virtual void display();
-
-    virtual void pageBackgroundTransparencyChanged();
-
-    virtual void attachCompositingContext();
-    virtual void detachCompositingContext();
-    virtual void setRootCompositingLayer(WebCore::GraphicsLayer*);
-    virtual void scheduleCompositingLayerSync();
-    virtual void syncCompositingLayers();
-
-    virtual void didReceiveMessage(CoreIPC::Connection*, CoreIPC::MessageID, CoreIPC::ArgumentDecoder*);
-
-private:
-
-    // GraphicsLayerClient
-    virtual void notifyAnimationStarted(const WebCore::GraphicsLayer*, double /*time*/) { }
-    virtual void notifySyncRequired(const WebCore::GraphicsLayer*) { }
-public:
-    virtual void paintContents(const WebCore::GraphicsLayer*, WebCore::GraphicsContext&, WebCore::GraphicsLayerPaintingPhase, const WebCore::IntRect& inClip);
-private:
-    virtual bool showDebugBorders() const;
-    virtual bool showRepaintCounter() const;
-
-#if PLATFORM(MAC)
-    virtual void onPageClose();
-#endif
-
-    void scheduleDisplay();
-    
-    // CoreIPC message handlers.
-    void setSize(const WebCore::IntSize& viewSize);
-    void suspendPainting();
-    void resumePainting();
-    void didUpdate();
-    
-    void platformInit();
-    void platformClear();
-
-#if PLATFORM(MAC)
-    void setUpUpdateLayoutRunLoopObserver();
-    void scheduleUpdateLayoutRunLoopObserver();
-    void removeUpdateLayoutRunLoopObserver();
-
-    static void updateLayoutRunLoopObserverCallback(CFRunLoopObserverRef, CFRunLoopActivity, void*);
-    void updateLayoutRunLoopObserverFired();
-#endif
-
-    RunLoop::Timer<LayerBackedDrawingArea> m_syncTimer;
-
-    OwnPtr<WebCore::GraphicsLayer> m_hostingLayer;
-    OwnPtr<WebCore::GraphicsLayer> m_backingLayer;
-#if PLATFORM(MAC)
-#if HAVE(HOSTED_CORE_ANIMATION)
-    RetainPtr<WKCARemoteLayerClientRef> m_remoteLayerRef;
-#endif
-    RetainPtr<CFRunLoopObserverRef> m_updateLayoutRunLoopObserver;
-#endif
-
-    bool m_attached;
-    bool m_shouldPaint;
-};
-
-} // namespace WebKit
-
-#endif // USE(ACCELERATED_COMPOSITING)
-
-#endif // LayerBackedDrawingArea_h
diff --git a/Source/WebKit2/WebProcess/WebPage/LayerTreeHost.h b/Source/WebKit2/WebProcess/WebPage/LayerTreeHost.h
index 4ca1137..bbb94e8 100644
--- a/Source/WebKit2/WebProcess/WebPage/LayerTreeHost.h
+++ b/Source/WebKit2/WebProcess/WebPage/LayerTreeHost.h
@@ -47,11 +47,13 @@ public:
 
     virtual const LayerTreeContext& layerTreeContext() = 0;
     virtual void scheduleLayerFlush() = 0;
+    virtual void setShouldNotifyAfterNextScheduledLayerFlush(bool) = 0;
     virtual void setRootCompositingLayer(WebCore::GraphicsLayer*) = 0;
     virtual void invalidate() = 0;
 
     virtual void setNonCompositedContentsNeedDisplay(const WebCore::IntRect&) = 0;
     virtual void scrollNonCompositedContents(const WebCore::IntRect& scrollRect, const WebCore::IntSize& scrollOffset) = 0;
+    virtual void forceRepaint() = 0;
     virtual void sizeDidChange(const WebCore::IntSize& newSize) = 0;
 
     virtual void didInstallPageOverlay() = 0;
diff --git a/Source/WebKit2/WebProcess/WebPage/TiledDrawingArea.cpp b/Source/WebKit2/WebProcess/WebPage/TiledDrawingArea.cpp
index f27f14f..5997564 100644
--- a/Source/WebKit2/WebProcess/WebPage/TiledDrawingArea.cpp
+++ b/Source/WebKit2/WebProcess/WebPage/TiledDrawingArea.cpp
@@ -43,8 +43,8 @@ using namespace WebCore;
 
 namespace WebKit {
 
-TiledDrawingArea::TiledDrawingArea(DrawingAreaInfo::Identifier identifier, WebPage* webPage)
-    : DrawingArea(DrawingAreaInfo::Tiled, identifier, webPage)
+TiledDrawingArea::TiledDrawingArea(WebPage* webPage)
+    : DrawingArea(DrawingAreaTypeTiled, webPage)
     , m_isWaitingForUpdate(false)
     , m_shouldPaint(true)
     , m_displayTimer(WebProcess::shared().runLoop(), this, &TiledDrawingArea::display)
diff --git a/Source/WebKit2/WebProcess/WebPage/TiledDrawingArea.h b/Source/WebKit2/WebProcess/WebPage/TiledDrawingArea.h
index 7b682ca..3572c9f 100644
--- a/Source/WebKit2/WebProcess/WebPage/TiledDrawingArea.h
+++ b/Source/WebKit2/WebProcess/WebPage/TiledDrawingArea.h
@@ -30,7 +30,6 @@
 
 #include "DrawingArea.h"
 #include "RunLoop.h"
-#include <WebCore/IntPoint.h>
 #include <WebCore/IntRect.h>
 #include <wtf/Vector.h>
 
@@ -40,7 +39,7 @@ class UpdateChunk;
 
 class TiledDrawingArea : public DrawingArea {
 public:
-    TiledDrawingArea(DrawingAreaInfo::Identifier, WebPage*);
+    explicit TiledDrawingArea(WebPage*);
     virtual ~TiledDrawingArea();
 
     virtual void setNeedsDisplay(const WebCore::IntRect&);
diff --git a/Source/WebKit2/WebProcess/WebPage/WebBackForwardListProxy.cpp b/Source/WebKit2/WebProcess/WebPage/WebBackForwardListProxy.cpp
index 7b958bf..02688c5 100644
--- a/Source/WebKit2/WebProcess/WebPage/WebBackForwardListProxy.cpp
+++ b/Source/WebKit2/WebProcess/WebPage/WebBackForwardListProxy.cpp
@@ -51,13 +51,13 @@ typedef HashMap<RefPtr<HistoryItem>, uint64_t> HistoryItemToIDMap;
 
 static IDToHistoryItemMap& idToHistoryItemMap()
 {
-    static IDToHistoryItemMap map;
+    DEFINE_STATIC_LOCAL(IDToHistoryItemMap, map, ());
     return map;
 } 
 
 static HistoryItemToIDMap& historyItemToIDMap()
 {
-    static HistoryItemToIDMap map;
+    DEFINE_STATIC_LOCAL(HistoryItemToIDMap, map, ());
     return map;
 } 
 
@@ -118,6 +118,12 @@ HistoryItem* WebBackForwardListProxy::itemForID(uint64_t itemID)
     return idToHistoryItemMap().get(itemID).get();
 }
 
+uint64_t WebBackForwardListProxy::idForItem(HistoryItem* item)
+{
+    ASSERT(item);
+    return historyItemToIDMap().get(item);
+}
+
 void WebBackForwardListProxy::removeItem(uint64_t itemID)
 {
     IDToHistoryItemMap::iterator it = idToHistoryItemMap().find(itemID);
diff --git a/Source/WebKit2/WebProcess/WebPage/WebBackForwardListProxy.h b/Source/WebKit2/WebProcess/WebPage/WebBackForwardListProxy.h
index be28739..00ef8f6 100644
--- a/Source/WebKit2/WebProcess/WebPage/WebBackForwardListProxy.h
+++ b/Source/WebKit2/WebProcess/WebPage/WebBackForwardListProxy.h
@@ -38,6 +38,7 @@ public:
     static PassRefPtr<WebBackForwardListProxy> create(WebPage* page) { return adoptRef(new WebBackForwardListProxy(page)); }
 
     static WebCore::HistoryItem* itemForID(uint64_t);
+    static uint64_t idForItem(WebCore::HistoryItem*);
     static void removeItem(uint64_t itemID);
 
     static void addItemFromUIProcess(uint64_t itemID, PassRefPtr<WebCore::HistoryItem>);
diff --git a/Source/WebKit2/WebProcess/WebPage/WebInspector.cpp b/Source/WebKit2/WebProcess/WebPage/WebInspector.cpp
index 4b3fdaf..58ae5ea 100644
--- a/Source/WebKit2/WebProcess/WebPage/WebInspector.cpp
+++ b/Source/WebKit2/WebProcess/WebPage/WebInspector.cpp
@@ -86,6 +86,11 @@ void WebInspector::didClose()
     WebProcess::shared().connection()->send(Messages::WebInspectorProxy::DidClose(), m_page->pageID());
 }
 
+void WebInspector::inspectedURLChanged(const String& urlString)
+{
+    WebProcess::shared().connection()->send(Messages::WebInspectorProxy::InspectedURLChanged(urlString), m_page->pageID());
+}
+
 // Called by WebInspector messages
 void WebInspector::show()
 {
diff --git a/Source/WebKit2/WebProcess/WebPage/WebInspector.h b/Source/WebKit2/WebProcess/WebPage/WebInspector.h
index 517ae8e..6b1c77a 100644
--- a/Source/WebKit2/WebProcess/WebPage/WebInspector.h
+++ b/Source/WebKit2/WebProcess/WebPage/WebInspector.h
@@ -73,6 +73,7 @@ private:
     // Called from WebInspectorFrontendClient
     void didLoadInspectorPage();
     void didClose();
+    void inspectedURLChanged(const String&);
 
     // Implemented in platform WebInspector file
     String localizedStringsURL() const;
diff --git a/Source/WebKit2/WebProcess/WebPage/WebPage.cpp b/Source/WebKit2/WebProcess/WebPage/WebPage.cpp
index 462d352..ff567bd 100644
--- a/Source/WebKit2/WebProcess/WebPage/WebPage.cpp
+++ b/Source/WebKit2/WebProcess/WebPage/WebPage.cpp
@@ -91,6 +91,7 @@
 #include <WebCore/RenderView.h>
 #include <WebCore/ReplaceSelectionCommand.h>
 #include <WebCore/ResourceRequest.h>
+#include <WebCore/SerializedScriptValue.h>
 #include <WebCore/Settings.h>
 #include <WebCore/SharedBuffer.h>
 #include <WebCore/SubstituteData.h>
@@ -99,6 +100,9 @@
 #include <runtime/JSLock.h>
 #include <runtime/JSValue.h>
 
+#include <WebCore/Range.h>
+#include <WebCore/VisiblePosition.h>
+
 #if PLATFORM(MAC) || PLATFORM(WIN)
 #include <WebCore/LegacyWebArchive.h>
 #endif
@@ -151,8 +155,11 @@ WebPage::WebPage(uint64_t pageID, const WebPageCreationParameters& parameters)
     , m_findController(this)
     , m_geolocationPermissionRequestManager(this)
     , m_pageID(pageID)
+    , m_canRunBeforeUnloadConfirmPanel(parameters.canRunBeforeUnloadConfirmPanel)
     , m_canRunModal(parameters.canRunModal)
     , m_isRunningModal(false)
+    , m_cachedMainFrameIsPinnedToLeftSide(false)
+    , m_cachedMainFrameIsPinnedToRightSide(false)
 {
     ASSERT(m_pageID);
 
@@ -184,7 +191,7 @@ WebPage::WebPage(uint64_t pageID, const WebPageCreationParameters& parameters)
     m_page->setGroupName(m_pageGroup->identifier());
 
     platformInitialize();
-    Settings::setMinDOMTimerInterval(0.004);
+    Settings::setDefaultMinDOMTimerInterval(0.004);
 
     m_drawingArea = DrawingArea::create(this, parameters);
     m_mainFrame = WebFrame::createMainFrame(this);
@@ -192,6 +199,8 @@ WebPage::WebPage(uint64_t pageID, const WebPageCreationParameters& parameters)
     setDrawsBackground(parameters.drawsBackground);
     setDrawsTransparentBackground(parameters.drawsTransparentBackground);
 
+    setMemoryCacheMessagesEnabled(parameters.areMemoryCacheClientCallsEnabled);
+
     setActive(parameters.isActive);
     setFocused(parameters.isFocused);
     setIsInWindow(parameters.isInWindow);
@@ -319,45 +328,13 @@ void WebPage::clearMainFrameName()
 }
 
 #if USE(ACCELERATED_COMPOSITING)
-void WebPage::changeAcceleratedCompositingMode(WebCore::GraphicsLayer* layer)
-{
-    if (m_isClosed)
-        return;
-
-    // With the new drawing area we don't need to inform the UI process when the accelerated
-    // compositing mode changes.
-    if (m_drawingArea->info().type == DrawingAreaInfo::Impl)
-        return;
-
-    bool compositing = layer;
-    
-    // Tell the UI process that accelerated compositing changed. It may respond by changing
-    // drawing area types.
-    DrawingAreaInfo newDrawingAreaInfo;
-
-    if (!sendSync(Messages::WebPageProxy::DidChangeAcceleratedCompositing(compositing), Messages::WebPageProxy::DidChangeAcceleratedCompositing::Reply(newDrawingAreaInfo)))
-        return;
-    
-    if (newDrawingAreaInfo.type != drawingArea()->info().type) {
-        m_drawingArea = 0;
-        if (newDrawingAreaInfo.type != DrawingAreaInfo::None) {
-            WebPageCreationParameters parameters;
-            parameters.drawingAreaInfo = newDrawingAreaInfo;
-            m_drawingArea = DrawingArea::create(this, parameters);
-            m_drawingArea->setNeedsDisplay(IntRect(IntPoint(0, 0), m_viewSize));
-        }
-    }
-}
-
 void WebPage::enterAcceleratedCompositingMode(GraphicsLayer* layer)
 {
-    changeAcceleratedCompositingMode(layer);
     m_drawingArea->setRootCompositingLayer(layer);
 }
 
 void WebPage::exitAcceleratedCompositingMode()
 {
-    changeAcceleratedCompositingMode(0);
     m_drawingArea->setRootCompositingLayer(0);
 }
 #endif
@@ -393,15 +370,16 @@ void WebPage::close()
     m_mainFrame->coreFrame()->loader()->detachFromParent();
     m_page.clear();
 
-    m_drawingArea->onPageClose();
     m_drawingArea.clear();
 
+    bool isRunningModal = m_isRunningModal;
+    m_isRunningModal = false;
+
+    // The WebPage can be destroyed by this call.
     WebProcess::shared().removeWebPage(m_pageID);
 
-    if (m_isRunningModal) {
-        m_isRunningModal = false;
+    if (isRunningModal)
         WebProcess::shared().runLoop()->stop();
-    }
 }
 
 void WebPage::tryClose()
@@ -482,25 +460,34 @@ void WebPage::reload(bool reloadFromOrigin)
 
 void WebPage::goForward(uint64_t backForwardItemID, const SandboxExtension::Handle& sandboxExtensionHandle)
 {
-    m_sandboxExtensionTracker.beginLoad(m_mainFrame.get(), sandboxExtensionHandle);
-
     HistoryItem* item = WebBackForwardListProxy::itemForID(backForwardItemID);
+    ASSERT(item);
+    if (!item)
+        return;
+
+    m_sandboxExtensionTracker.beginLoad(m_mainFrame.get(), sandboxExtensionHandle);
     m_page->goToItem(item, FrameLoadTypeForward);
 }
 
 void WebPage::goBack(uint64_t backForwardItemID, const SandboxExtension::Handle& sandboxExtensionHandle)
 {
-    m_sandboxExtensionTracker.beginLoad(m_mainFrame.get(), sandboxExtensionHandle);
-
     HistoryItem* item = WebBackForwardListProxy::itemForID(backForwardItemID);
+    ASSERT(item);
+    if (!item)
+        return;
+
+    m_sandboxExtensionTracker.beginLoad(m_mainFrame.get(), sandboxExtensionHandle);
     m_page->goToItem(item, FrameLoadTypeBack);
 }
 
 void WebPage::goToBackForwardItem(uint64_t backForwardItemID, const SandboxExtension::Handle& sandboxExtensionHandle)
 {
-    m_sandboxExtensionTracker.beginLoad(m_mainFrame.get(), sandboxExtensionHandle);
-
     HistoryItem* item = WebBackForwardListProxy::itemForID(backForwardItemID);
+    ASSERT(item);
+    if (!item)
+        return;
+
+    m_sandboxExtensionTracker.beginLoad(m_mainFrame.get(), sandboxExtensionHandle);
     m_page->goToItem(item, FrameLoadTypeIndexedBackForward);
 }
 
@@ -603,10 +590,6 @@ void WebPage::drawRect(GraphicsContext& graphicsContext, const IntRect& rect)
     graphicsContext.clip(rect);
     m_mainFrame->coreFrame()->view()->paint(&graphicsContext, rect);
     graphicsContext.restore();
-
-    // FIXME: Remove this code once we're using the new drawing area on mac and windows.
-    if (m_pageOverlay && m_drawingArea->info().type != DrawingAreaInfo::Impl)
-        drawPageOverlay(graphicsContext, rect);
 }
 
 void WebPage::drawPageOverlay(GraphicsContext& graphicsContext, const IntRect& rect)
@@ -999,7 +982,7 @@ void WebPage::gestureEvent(const WebGestureEvent& gestureEvent)
 }
 #endif
 
-void WebPage::validateMenuItem(const String& commandName)
+void WebPage::validateCommand(const String& commandName, uint64_t callbackID)
 {
     bool isEnabled = false;
     int32_t state = 0;
@@ -1010,7 +993,7 @@ void WebPage::validateMenuItem(const String& commandName)
         isEnabled = command.isSupported() && command.isEnabled();
     }
 
-    send(Messages::WebPageProxy::DidValidateMenuItem(commandName, isEnabled, state));
+    send(Messages::WebPageProxy::ValidateCommandCallback(commandName, isEnabled, state, callbackID));
 }
 
 void WebPage::executeEditCommand(const String& commandName)
@@ -1209,18 +1192,29 @@ IntRect WebPage::windowResizerRect() const
                    m_windowResizerSize.width(), m_windowResizerSize.height());
 }
 
+KeyboardUIMode WebPage::keyboardUIMode()
+{
+    bool fullKeyboardAccessEnabled = WebProcess::shared().fullKeyboardAccessEnabled();
+    return static_cast<KeyboardUIMode>((fullKeyboardAccessEnabled ? KeyboardAccessFull : KeyboardAccessDefault) | (m_tabToLinks ? KeyboardAccessTabsToLinks : 0));
+}
+
 void WebPage::runJavaScriptInMainFrame(const String& script, uint64_t callbackID)
 {
     // NOTE: We need to be careful when running scripts that the objects we depend on don't
     // disappear during script execution.
 
+    // Retain the SerializedScriptValue at this level so it (and the internal data) lives
+    // long enough for the DataReference to be encoded by the sent message.
+    RefPtr<SerializedScriptValue> serializedResultValue;
+    CoreIPC::DataReference dataReference;
+
     JSLock lock(SilenceAssertionsOnly);
-    JSValue resultValue = m_mainFrame->coreFrame()->script()->executeScript(script, true).jsValue();
-    String resultString;
-    if (resultValue)
-        resultString = ustringToString(resultValue.toString(m_mainFrame->coreFrame()->script()->globalObject(mainThreadNormalWorld())->globalExec()));
+    if (JSValue resultValue = m_mainFrame->coreFrame()->script()->executeScript(script, true).jsValue()) {
+        if ((serializedResultValue = SerializedScriptValue::create(m_mainFrame->coreFrame()->script()->globalObject(mainThreadNormalWorld())->globalExec(), resultValue)))
+            dataReference = CoreIPC::DataReference(serializedResultValue->data().data(), serializedResultValue->data().size());
+    }
 
-    send(Messages::WebPageProxy::StringCallback(resultString, callbackID));
+    send(Messages::WebPageProxy::ScriptValueCallback(dataReference, callbackID));
 }
 
 void WebPage::getContentsAsString(uint64_t callbackID)
@@ -1291,7 +1285,7 @@ void WebPage::getWebArchiveOfFrame(uint64_t frameID, uint64_t callbackID)
 #if PLATFORM(MAC) || PLATFORM(WIN)
     RetainPtr<CFDataRef> data;
     if (WebFrame* frame = WebProcess::shared().webFrame(frameID)) {
-        if (RefPtr<LegacyWebArchive> archive = LegacyWebArchive::create(frame->coreFrame())) {
+        if (RefPtr<LegacyWebArchive> archive = LegacyWebArchive::create(frame->coreFrame()->document())) {
             if ((data = archive->rawDataRepresentation()))
                 dataReference = CoreIPC::DataReference(CFDataGetBytePtr(data.get()), CFDataGetLength(data.get()));
         }
@@ -1301,12 +1295,17 @@ void WebPage::getWebArchiveOfFrame(uint64_t frameID, uint64_t callbackID)
     send(Messages::WebPageProxy::DataCallback(dataReference, callbackID));
 }
 
-void WebPage::forceRepaint(uint64_t callbackID)
+void WebPage::forceRepaintWithoutCallback()
 {
     m_drawingArea->forceRepaint();
+}
+
+void WebPage::forceRepaint(uint64_t callbackID)
+{
+    forceRepaintWithoutCallback();
     send(Messages::WebPageProxy::VoidCallback(callbackID));
 }
-    
+
 void WebPage::preferencesDidChange(const WebPreferencesStore& store)
 {
     WebPreferencesStore::removeTestRunnerOverrides();
@@ -1363,8 +1362,10 @@ void WebPage::updatePreferences(const WebPreferencesStore& store)
 #if PLATFORM(WIN)
     // Temporarily turn off accelerated compositing until we have a good solution for rendering it.
     settings->setAcceleratedCompositingEnabled(false);
+    settings->setAcceleratedDrawingEnabled(false);
 #else
     settings->setAcceleratedCompositingEnabled(store.getBoolValueForKey(WebPreferencesKey::acceleratedCompositingEnabledKey()));
+    settings->setAcceleratedDrawingEnabled(store.getBoolValueForKey(WebPreferencesKey::acceleratedDrawingEnabledKey()));
 #endif
     settings->setShowDebugBorders(store.getBoolValueForKey(WebPreferencesKey::compositingBordersVisibleKey()));
     settings->setShowRepaintCounter(store.getBoolValueForKey(WebPreferencesKey::compositingRepaintCountersVisibleKey()));
@@ -1664,9 +1665,9 @@ void WebPage::replaceSelectionWithText(Frame* frame, const String& text)
 {
     if (frame->selection()->isNone())
         return;
-    
+
     RefPtr<DocumentFragment> textFragment = createFragmentFromText(frame->selection()->toNormalizedRange().get(), text);
-    applyCommand(ReplaceSelectionCommand::create(frame->document(), textFragment.release(), true, false, true));
+    applyCommand(ReplaceSelectionCommand::create(frame->document(), textFragment.release(), ReplaceSelectionCommand::SelectReplacement | ReplaceSelectionCommand::MatchStyle | ReplaceSelectionCommand::PreventNesting));
     frame->selection()->revealSelection(ScrollAlignment::alignToEdgeIfNeeded);
 }
 
@@ -1675,6 +1676,23 @@ bool WebPage::mainFrameHasCustomRepresentation() const
     return static_cast<WebFrameLoaderClient*>(mainFrame()->coreFrame()->loader()->client())->frameHasCustomRepresentation();
 }
 
+void WebPage::didChangeScrollOffsetForMainFrame()
+{
+    Frame* frame = m_page->mainFrame();
+    IntPoint scrollPosition = frame->view()->scrollPosition();
+    IntPoint maximumScrollPosition = frame->view()->maximumScrollPosition();
+
+    bool isPinnedToLeftSide = (scrollPosition.x() <= 0);
+    bool isPinnedToRightSide = (scrollPosition.x() >= maximumScrollPosition.x());
+
+    if (isPinnedToLeftSide != m_cachedMainFrameIsPinnedToLeftSide || isPinnedToRightSide != m_cachedMainFrameIsPinnedToRightSide) {
+        send(Messages::WebPageProxy::DidChangeScrollOffsetPinningForMainFrame(isPinnedToLeftSide, isPinnedToRightSide));
+        
+        m_cachedMainFrameIsPinnedToLeftSide = isPinnedToLeftSide;
+        m_cachedMainFrameIsPinnedToRightSide = isPinnedToRightSide;
+    }
+}
+
 #if PLATFORM(MAC)
 
 void WebPage::addPluginView(PluginView* pluginView)
@@ -1969,8 +1987,7 @@ void WebPage::computePagesForPrinting(uint64_t frameID, const PrintInfo& printIn
     send(Messages::WebPageProxy::ComputedPagesCallback(resultPageRects, resultTotalScaleFactorForPrinting, callbackID));
 }
 
-#if PLATFORM(MAC)
-// FIXME: Find a better place for Mac specific code.
+#if PLATFORM(MAC) || PLATFORM(WIN)
 void WebPage::drawRectToPDF(uint64_t frameID, const WebCore::IntRect& rect, uint64_t callbackID)
 {
     WebFrame* frame = WebProcess::shared().webFrame(frameID);
@@ -2050,4 +2067,9 @@ void WebPage::runModal()
     ASSERT(!m_isRunningModal);
 }
 
+void WebPage::setMemoryCacheMessagesEnabled(bool memoryCacheMessagesEnabled)
+{
+    m_page->setMemoryCacheClientCallsEnabled(memoryCacheMessagesEnabled);
+}
+
 } // namespace WebKit
diff --git a/Source/WebKit2/WebProcess/WebPage/WebPage.h b/Source/WebKit2/WebProcess/WebPage/WebPage.h
index 89087b0..8ce6405 100644
--- a/Source/WebKit2/WebProcess/WebPage/WebPage.h
+++ b/Source/WebKit2/WebProcess/WebPage/WebPage.h
@@ -46,6 +46,7 @@
 #include <WebCore/Editor.h>
 #include <WebCore/FrameLoaderTypes.h>
 #include <WebCore/IntRect.h>
+#include <WebCore/WebCoreKeyboardUIMode.h>
 #include <wtf/HashMap.h>
 #include <wtf/OwnPtr.h>
 #include <wtf/PassRefPtr.h>
@@ -57,6 +58,7 @@
 #endif
 
 #if PLATFORM(MAC)
+#include "DictionaryPopupInfo.h"
 #include <wtf/RetainPtr.h>
 OBJC_CLASS AccessibilityWebPageObject;
 #endif
@@ -72,6 +74,7 @@ namespace WebCore {
     class KeyboardEvent;
     class Page;
     class PrintContext;
+    class Range;
     class ResourceRequest;
     class SharedBuffer;
 }
@@ -151,7 +154,7 @@ public:
     void show();
     String userAgent() const { return m_userAgent; }
     WebCore::IntRect windowResizerRect() const;
-    bool tabsToLinks() const { return m_tabToLinks; }
+    WebCore::KeyboardUIMode keyboardUIMode();
 
     WebEditCommand* webEditCommand(uint64_t);
     void addWebEditCommand(uint64_t, WebEditCommand*);
@@ -215,7 +218,6 @@ public:
     void setDefersLoading(bool deferLoading);
 
 #if USE(ACCELERATED_COMPOSITING)
-    void changeAcceleratedCompositingMode(WebCore::GraphicsLayer*);
     void enterAcceleratedCompositingMode(WebCore::GraphicsLayer*);
     void exitAcceleratedCompositingMode();
 #endif
@@ -294,6 +296,7 @@ public:
     void getMarkedRange(uint64_t& location, uint64_t& length);
     void characterIndexForPoint(const WebCore::IntPoint point, uint64_t& result);
     void firstRectForCharacterRange(uint64_t location, uint64_t length, WebCore::IntRect& resultRect);
+    void writeSelectionToPasteboard(const WTF::String& pasteboardName, const WTF::Vector<WTF::String>& pasteboardTypes, bool& result);
 #elif PLATFORM(WIN)
     void confirmComposition(const String& compositionString);
     void setComposition(const WTF::String& compositionString, const WTF::Vector<WebCore::CompositionUnderline>& underlines, uint64_t cursorPosition);
@@ -306,6 +309,8 @@ public:
     void dummy(bool&);
 
 #if PLATFORM(MAC)
+    void performDictionaryLookupForRange(DictionaryPopupInfo::Type, WebCore::Frame*, WebCore::Range*);
+
     bool isSpeaking();
     void speak(const String&);
     void stopSpeaking();
@@ -324,16 +329,27 @@ public:
     void beginPrinting(uint64_t frameID, const PrintInfo&);
     void endPrinting();
     void computePagesForPrinting(uint64_t frameID, const PrintInfo&, uint64_t callbackID);
-#if PLATFORM(MAC)
+#if PLATFORM(MAC) || PLATFORM(WIN)
     void drawRectToPDF(uint64_t frameID, const WebCore::IntRect&, uint64_t callbackID);
     void drawPagesToPDF(uint64_t frameID, uint32_t first, uint32_t count, uint64_t callbackID);
 #endif
 
     bool mainFrameHasCustomRepresentation() const;
 
+    void didChangeScrollOffsetForMainFrame();
+
+    bool canRunBeforeUnloadConfirmPanel() const { return m_canRunBeforeUnloadConfirmPanel; }
+    void setCanRunBeforeUnloadConfirmPanel(bool canRunBeforeUnloadConfirmPanel) { m_canRunBeforeUnloadConfirmPanel = canRunBeforeUnloadConfirmPanel; }
+
     bool canRunModal() const { return m_canRunModal; }
+    void setCanRunModal(bool canRunModal) { m_canRunModal = canRunModal; }
+
     void runModal();
 
+    void setMemoryCacheMessagesEnabled(bool);
+
+    void forceRepaintWithoutCallback();
+
 private:
     WebPage(uint64_t pageID, const WebPageCreationParameters&);
 
@@ -369,7 +385,7 @@ private:
     void setInitialFocus(bool);
     void setWindowResizerSize(const WebCore::IntSize&);
     void setIsInWindow(bool);
-    void validateMenuItem(const String&);
+    void validateCommand(const String&, uint64_t);
     void executeEditCommand(const String&);
 
     void mouseEvent(const WebMouseEvent&);
@@ -412,6 +428,8 @@ private:
     void setCustomTextEncodingName(const String&);
 
 #if PLATFORM(MAC)
+    void performDictionaryLookupAtLocation(const WebCore::FloatPoint&);
+
     void setWindowIsVisible(bool windowIsVisible);
     void windowAndViewFramesChanged(const WebCore::IntRect& windowFrameInScreenCoordinates, const WebCore::IntRect& viewFrameInWindowCoordinates, const WebCore::IntPoint& accessibilityViewCoordinates);
 #endif
@@ -464,7 +482,7 @@ private:
     String m_userAgent;
 
     WebCore::IntSize m_viewSize;
-    RefPtr<DrawingArea> m_drawingArea;
+    OwnPtr<DrawingArea> m_drawingArea;
 
     bool m_drawsBackground;
     bool m_drawsTransparentBackground;
@@ -531,8 +549,13 @@ private:
     SandboxExtensionTracker m_sandboxExtensionTracker;
     uint64_t m_pageID;
 
+    bool m_canRunBeforeUnloadConfirmPanel;
+
     bool m_canRunModal;
     bool m_isRunningModal;
+
+    bool m_cachedMainFrameIsPinnedToLeftSide;
+    bool m_cachedMainFrameIsPinnedToRightSide;
 };
 
 } // namespace WebKit
diff --git a/Source/WebKit2/WebProcess/WebPage/WebPage.messages.in b/Source/WebKit2/WebProcess/WebPage/WebPage.messages.in
index e47a013..0c0eea5 100644
--- a/Source/WebKit2/WebProcess/WebPage/WebPage.messages.in
+++ b/Source/WebKit2/WebProcess/WebPage/WebPage.messages.in
@@ -70,10 +70,13 @@ messages -> WebPage {
     GetSourceForFrame(uint64_t frameID, uint64_t callbackID)
     GetWebArchiveOfFrame(uint64_t frameID, uint64_t callbackID)
     RunJavaScriptInMainFrame(WTF::String script, uint64_t callbackID)
-
-    # FIXME: This should be a drawing area message.
     ForceRepaint(uint64_t callbackID)
 
+#if PLATFORM(MAC)
+    # Dictionary support.
+    PerformDictionaryLookupAtLocation(WebCore::FloatPoint point)
+#endif
+
     PreferencesDidChange(WebKit::WebPreferencesStore store)
 
     SetUserAgent(WTF::String userAgent)
@@ -87,7 +90,7 @@ messages -> WebPage {
     Close()
     TryClose()
 
-    ValidateMenuItem(WTF::String name)
+    ValidateCommand(WTF::String name, uint64_t callbackID)
     ExecuteEditCommand(WTF::String name)
 
     DidRemoveEditCommand(uint64_t commandID)
@@ -153,15 +156,20 @@ messages -> WebPage {
     BeginPrinting(uint64_t frameID, WebKit::PrintInfo printInfo)
     EndPrinting();
     ComputePagesForPrinting(uint64_t frameID, WebKit::PrintInfo printInfo, uint64_t callbackID)
-#if PLATFORM(MAC)
+#if PLATFORM(MAC) || PLATFORM(WIN)
     DrawRectToPDF(uint64_t frameID, WebCore::IntRect rect, uint64_t callbackID)
     DrawPagesToPDF(uint64_t frameID, uint32_t first, uint32_t count, uint64_t callbackID)
 #endif
 
+    SetMemoryCacheMessagesEnabled(bool memoryCacheMessagesEnabled)
+
     // FIXME: This a dummy message, to avoid breaking the build for platforms that don't require
     // any synchronous messages, and should be removed when <rdar://problem/8775115> is fixed.
     Dummy() -> (bool dummyReturn)
 
+    SetCanRunBeforeUnloadConfirmPanel(bool canRunBeforeUnloadConfirmPanel)
+    SetCanRunModal(bool canRunModal)
+
 #if PLATFORM(MAC)
     # Complex text input support for plug-ins.
     SendComplexTextInputToPlugin(uint64_t pluginComplexTextInputIdentifier, String textInput)
@@ -172,6 +180,7 @@ messages -> WebPage {
     CharacterIndexForPoint(WebCore::IntPoint point) -> (uint64_t result)
     FirstRectForCharacterRange(uint64_t location, uint64_t length) -> (WebCore::IntRect resultRect)
     RegisterUIProcessAccessibilityTokens(CoreIPC::DataReference elemenToken, CoreIPC::DataReference windowToken)
+    WriteSelectionToPasteboard(WTF::String pasteboardName, WTF::Vector<WTF::String> pasteboardTypes) -> (bool result)
 #endif
 #if PLATFORM(WIN)
     ConfirmComposition(WTF::String compositionString)
diff --git a/Source/WebKit2/WebProcess/WebPage/gtk/WebInspectorGtk.cpp b/Source/WebKit2/WebProcess/WebPage/gtk/WebInspectorGtk.cpp
index 36bde01..e00e437 100644
--- a/Source/WebKit2/WebProcess/WebPage/gtk/WebInspectorGtk.cpp
+++ b/Source/WebKit2/WebProcess/WebPage/gtk/WebInspectorGtk.cpp
@@ -29,11 +29,9 @@
 
 #if ENABLE(INSPECTOR)
 
+#include <WebCore/NotImplemented.h>
 #include <wtf/text/WTFString.h>
 
-#define DISABLE_NOT_IMPLEMENTED_WARNINGS 1
-#include "NotImplemented.h"
-
 namespace WebKit {
 
 String WebInspector::localizedStringsURL() const
diff --git a/Source/WebKit2/WebProcess/WebPage/mac/LayerBackedDrawingAreaMac.mm b/Source/WebKit2/WebProcess/WebPage/mac/LayerBackedDrawingAreaMac.mm
deleted file mode 100644
index 25a1dfd..0000000
--- a/Source/WebKit2/WebProcess/WebPage/mac/LayerBackedDrawingAreaMac.mm
+++ /dev/null
@@ -1,187 +0,0 @@
-/*
- * Copyright (C) 2010 Apple Inc. All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- * 1. Redistributions of source code must retain the above copyright
- *    notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- *    notice, this list of conditions and the following disclaimer in the
- *    documentation and/or other materials provided with the distribution.
- *
- * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
- * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
- * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
- * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
- * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
- * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
- * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
- * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
- * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
- * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
- * THE POSSIBILITY OF SUCH DAMAGE.
- */
-
-#import "config.h"
-#import "LayerBackedDrawingArea.h"
-
-#if USE(ACCELERATED_COMPOSITING)
-
-#import "DrawingAreaProxyMessageKinds.h"
-#import "WebKitSystemInterface.h"
-#import "WebPage.h"
-#import "WebProcess.h"
-#import <WebCore/Frame.h>
-#import <WebCore/FrameView.h>
-#import <WebCore/GraphicsLayer.h>
-#import <WebCore/Page.h>
-
-using namespace WebCore;
-
-namespace WebKit {
-
-void LayerBackedDrawingArea::platformInit()
-{
-    setUpUpdateLayoutRunLoopObserver();
-
-    [m_hostingLayer->platformLayer() setGeometryFlipped:YES];
-#if HAVE(HOSTED_CORE_ANIMATION)
-    attachCompositingContext();
-#endif
-
-    scheduleCompositingLayerSync();
-}
-
-void LayerBackedDrawingArea::platformClear()
-{
-    if (!m_attached)
-        return;
-
-    if (m_updateLayoutRunLoopObserver) {
-        CFRunLoopObserverInvalidate(m_updateLayoutRunLoopObserver.get());
-        m_updateLayoutRunLoopObserver = 0;
-    }
-
-#if HAVE(HOSTED_CORE_ANIMATION)
-    WKCARemoteLayerClientInvalidate(m_remoteLayerRef.get());
-    m_remoteLayerRef = nullptr;
-#endif
-
-    m_attached = false;
-}
-
-void LayerBackedDrawingArea::attachCompositingContext()
-{
-    if (m_attached)
-        return;
-
-    m_attached = true;
-
-#if HAVE(HOSTED_CORE_ANIMATION)
-    mach_port_t serverPort = WebProcess::shared().compositingRenderServerPort();
-    m_remoteLayerRef = WKCARemoteLayerClientMakeWithServerPort(serverPort);
-    WKCARemoteLayerClientSetLayer(m_remoteLayerRef.get(), m_hostingLayer->platformLayer());
-    
-    uint32_t contextID = WKCARemoteLayerClientGetClientId(m_remoteLayerRef.get());
-    WebProcess::shared().connection()->deprecatedSendSync(DrawingAreaProxyLegacyMessage::AttachCompositingContext, m_webPage->pageID(), CoreIPC::In(contextID), CoreIPC::Out());
-#endif
-}
-
-void LayerBackedDrawingArea::detachCompositingContext()
-{
-    m_backingLayer->removeAllChildren();
-
-    scheduleCompositingLayerSync();
-}
-
-void LayerBackedDrawingArea::setRootCompositingLayer(WebCore::GraphicsLayer* layer)
-{
-    m_backingLayer->removeAllChildren();
-    if (layer)
-        m_backingLayer->addChild(layer);
-
-    scheduleCompositingLayerSync();
-}
-
-void LayerBackedDrawingArea::scheduleCompositingLayerSync()
-{
-//    if (m_syncTimer.isActive())
-//        return;
-//
-//    m_syncTimer.startOneShot(0);
-
-    scheduleUpdateLayoutRunLoopObserver();
-}
-
-void LayerBackedDrawingArea::syncCompositingLayers()
-{
-    m_hostingLayer->syncCompositingStateForThisLayerOnly();
-    m_backingLayer->syncCompositingStateForThisLayerOnly();
-
-    bool didSync = m_webPage->corePage()->mainFrame()->view()->syncCompositingStateIncludingSubframes();
-    if (!didSync) {
-    
-    }
-}
-
-void LayerBackedDrawingArea::setUpUpdateLayoutRunLoopObserver()
-{
-    if (m_updateLayoutRunLoopObserver)
-        return;
-
-    // Run before Core Animations commit observer, which has order 2000000.
-    const CFIndex runLoopOrder = 2000000 - 1;
-    CFRunLoopObserverContext context = { 0, this, 0, 0, 0 };
-    m_updateLayoutRunLoopObserver.adoptCF(CFRunLoopObserverCreate(0,
-        kCFRunLoopBeforeWaiting | kCFRunLoopExit, true /* repeats */,
-        runLoopOrder, updateLayoutRunLoopObserverCallback, &context));
-}
-
-void LayerBackedDrawingArea::scheduleUpdateLayoutRunLoopObserver()
-{
-    CFRunLoopRef currentRunLoop = CFRunLoopGetCurrent();
-    CFRunLoopWakeUp(currentRunLoop);
-
-    if (CFRunLoopContainsObserver(currentRunLoop, m_updateLayoutRunLoopObserver.get(), kCFRunLoopCommonModes))
-        return;
-
-    CFRunLoopAddObserver(currentRunLoop, m_updateLayoutRunLoopObserver.get(), kCFRunLoopCommonModes);
-}
-
-void LayerBackedDrawingArea::removeUpdateLayoutRunLoopObserver()
-{
-    // FIXME: cache the run loop ref?
-    CFRunLoopRemoveObserver(CFRunLoopGetCurrent(), m_updateLayoutRunLoopObserver.get(), kCFRunLoopCommonModes);
-}
-
-void LayerBackedDrawingArea::updateLayoutRunLoopObserverCallback(CFRunLoopObserverRef, CFRunLoopActivity, void* info)
-{
-    // Keep the drawing area alive while running the callback, since that does layout,
-    // which might replace this drawing area with one of another type.
-    RefPtr<LayerBackedDrawingArea> drawingArea = reinterpret_cast<LayerBackedDrawingArea*>(info);
-    drawingArea->updateLayoutRunLoopObserverFired();
-}
-
-void LayerBackedDrawingArea::updateLayoutRunLoopObserverFired()
-{
-    // Laying out the page can cause the drawing area to change so we keep an extra reference.
-    RefPtr<LayerBackedDrawingArea> protect(this);
-
-    m_webPage->layoutIfNeeded();
-
-    if (m_webPage->drawingArea() != this)
-        return;
-    
-    if (m_attached)
-        syncCompositingLayers();
-}
-
-void LayerBackedDrawingArea::onPageClose()
-{
-    platformClear();
-}
-
-} // namespace WebKit
-
-#endif // USE(ACCELERATED_COMPOSITING)
diff --git a/Source/WebKit2/WebProcess/WebPage/mac/LayerTreeHostMac.h b/Source/WebKit2/WebProcess/WebPage/mac/LayerTreeHostMac.h
index 016f0d6..d05e43e 100644
--- a/Source/WebKit2/WebProcess/WebPage/mac/LayerTreeHostMac.h
+++ b/Source/WebKit2/WebProcess/WebPage/mac/LayerTreeHostMac.h
@@ -47,12 +47,14 @@ private:
     // LayerTreeHost.
     virtual const LayerTreeContext& layerTreeContext();
     virtual void scheduleLayerFlush();
+    virtual void setShouldNotifyAfterNextScheduledLayerFlush(bool);
     virtual void setRootCompositingLayer(WebCore::GraphicsLayer*);
     virtual void invalidate();
 
     virtual void setNonCompositedContentsNeedDisplay(const WebCore::IntRect&);
     virtual void scrollNonCompositedContents(const WebCore::IntRect& scrollRect, const WebCore::IntSize& scrollOffset);
     virtual void sizeDidChange(const WebCore::IntSize& newSize);
+    virtual void forceRepaint();
 
     virtual void didInstallPageOverlay();
     virtual void didUninstallPageOverlay();
@@ -78,6 +80,10 @@ private:
     // Whether the layer tree host is valid or not.
     bool m_isValid;    
 
+    // Whether we should let the drawing area know the next time we've flushed
+    // layer tree changes.
+    bool m_notifyAfterScheduledLayerFlush;
+    
     // The root layer.
     OwnPtr<WebCore::GraphicsLayer> m_rootLayer;
 
diff --git a/Source/WebKit2/WebProcess/WebPage/mac/LayerTreeHostMac.mm b/Source/WebKit2/WebProcess/WebPage/mac/LayerTreeHostMac.mm
index 9734aec..494f5e6 100644
--- a/Source/WebKit2/WebProcess/WebPage/mac/LayerTreeHostMac.mm
+++ b/Source/WebKit2/WebProcess/WebPage/mac/LayerTreeHostMac.mm
@@ -26,6 +26,7 @@
 #import "config.h"
 #import "LayerTreeHostMac.h"
 
+#import "DrawingAreaImpl.h"
 #import "WebPage.h"
 #import "WebProcess.h"
 #import <QuartzCore/CATransaction.h>
@@ -51,6 +52,7 @@ PassRefPtr<LayerTreeHostMac> LayerTreeHostMac::create(WebPage* webPage)
 LayerTreeHostMac::LayerTreeHostMac(WebPage* webPage)
     : LayerTreeHost(webPage)
     , m_isValid(true)
+    , m_notifyAfterScheduledLayerFlush(false)
 {
     mach_port_t serverPort = WebProcess::shared().compositingRenderServerPort();
     m_remoteLayerClient = WKCARemoteLayerClientMakeWithServerPort(serverPort);
@@ -72,6 +74,8 @@ LayerTreeHostMac::LayerTreeHostMac(WebPage* webPage)
     m_nonCompositedContentLayer->setDrawsContent(true);
     m_nonCompositedContentLayer->setContentsOpaque(m_webPage->drawsBackground() && !m_webPage->drawsTransparentBackground());
     m_nonCompositedContentLayer->setSize(webPage->size());
+    if (m_webPage->corePage()->settings()->acceleratedDrawingEnabled())
+        m_nonCompositedContentLayer->setAcceleratesDrawing(true);
 
     m_rootLayer->addChild(m_nonCompositedContentLayer.get());
 
@@ -116,14 +120,18 @@ void LayerTreeHostMac::scheduleLayerFlush()
     CFRunLoopAddObserver(currentRunLoop, m_flushPendingLayerChangesRunLoopObserver.get(), kCFRunLoopCommonModes);
 }
 
-void LayerTreeHostMac::setRootCompositingLayer(GraphicsLayer* graphicsLayer)
+void LayerTreeHostMac::setShouldNotifyAfterNextScheduledLayerFlush(bool notifyAfterScheduledLayerFlush)
 {
-    ASSERT(graphicsLayer);
+    m_notifyAfterScheduledLayerFlush = notifyAfterScheduledLayerFlush;
+}
 
+void LayerTreeHostMac::setRootCompositingLayer(GraphicsLayer* graphicsLayer)
+{
     m_nonCompositedContentLayer->removeAllChildren();
 
     // Add the accelerated layer tree hierarchy.
-    m_nonCompositedContentLayer->addChild(graphicsLayer);
+    if (graphicsLayer)
+        m_nonCompositedContentLayer->addChild(graphicsLayer);
 }
 
 void LayerTreeHostMac::invalidate()
@@ -170,6 +178,15 @@ void LayerTreeHostMac::sizeDidChange(const IntSize& newSize)
     [CATransaction synchronize];
 }
 
+void LayerTreeHostMac::forceRepaint()
+{
+    scheduleLayerFlush();
+    flushPendingLayerChanges();
+
+    [CATransaction flush];
+    [CATransaction synchronize];
+}    
+
 void LayerTreeHostMac::didInstallPageOverlay()
 {
     createPageOverlayLayer();
@@ -242,6 +259,12 @@ void LayerTreeHostMac::flushPendingLayerChangesRunLoopObserverCallback()
     ASSERT(m_flushPendingLayerChangesRunLoopObserver);
     CFRunLoopObserverInvalidate(m_flushPendingLayerChangesRunLoopObserver.get());
     m_flushPendingLayerChangesRunLoopObserver = 0;
+
+    if (m_notifyAfterScheduledLayerFlush) {
+        // Let the drawing area know that we've done a flush of the layer changes.
+        static_cast<DrawingAreaImpl*>(m_webPage->drawingArea())->layerHostDidFlushLayers();
+        m_notifyAfterScheduledLayerFlush = false;
+    }
 }
 
 bool LayerTreeHostMac::flushPendingLayerChanges()
diff --git a/Source/WebKit2/WebProcess/WebPage/mac/WebPageMac.mm b/Source/WebKit2/WebProcess/WebPage/mac/WebPageMac.mm
index 71bbf78..4cae5aa 100644
--- a/Source/WebKit2/WebProcess/WebPage/mac/WebPageMac.mm
+++ b/Source/WebKit2/WebProcess/WebPage/mac/WebPageMac.mm
@@ -42,6 +42,7 @@
 #import <WebCore/KeyboardEvent.h>
 #import <WebCore/Page.h>
 #import <WebCore/PlatformKeyboardEvent.h>
+#import <WebCore/ResourceHandle.h>
 #import <WebCore/ScrollView.h>
 #import <WebCore/TextIterator.h>
 #import <WebCore/WindowsKeyboardCodes.h>
@@ -163,29 +164,29 @@ void WebPage::getMarkedRange(uint64_t& location, uint64_t& length)
     getLocationAndLengthFromRange(frame->editor()->compositionRange().get(), location, length);
 }
 
-static Range *characterRangeAtPoint(Frame* frame, const IntPoint point)
+static PassRefPtr<Range> characterRangeAtPoint(Frame* frame, const IntPoint& point)
 {
     VisiblePosition position = frame->visiblePositionForPoint(point);
     if (position.isNull())
-        return NULL;
+        return 0;
     
     VisiblePosition previous = position.previous();
     if (previous.isNotNull()) {
-        Range *previousCharacterRange = makeRange(previous, position).get();
-        NSRect rect = frame->editor()->firstRectForRange(previousCharacterRange);
-        if (NSPointInRect(point, rect))
-            return previousCharacterRange;
+        RefPtr<Range> previousCharacterRange = makeRange(previous, position);
+        IntRect rect = frame->editor()->firstRectForRange(previousCharacterRange.get());
+        if (rect.contains(point))
+            return previousCharacterRange.release();
     }
     
     VisiblePosition next = position.next();
     if (next.isNotNull()) {
-        Range *nextCharacterRange = makeRange(position, next).get();
-        NSRect rect = frame->editor()->firstRectForRange(nextCharacterRange);
-        if (NSPointInRect(point, rect))
-            return nextCharacterRange;
+        RefPtr<Range> nextCharacterRange = makeRange(position, next);
+        IntRect rect = frame->editor()->firstRectForRange(nextCharacterRange.get());
+        if (rect.contains(point))
+            return nextCharacterRange.release();
     }
     
-    return NULL;
+    return 0;
 }
     
 void WebPage::characterIndexForPoint(IntPoint point, uint64_t& index)
@@ -198,12 +199,12 @@ void WebPage::characterIndexForPoint(IntPoint point, uint64_t& index)
     HitTestResult result = frame->eventHandler()->hitTestResultAtPoint(point, false);
     frame = result.innerNonSharedNode() ? result.innerNonSharedNode()->document()->frame() : m_page->focusController()->focusedOrMainFrame();
     
-    Range *range = characterRangeAtPoint(frame, result.point());
+    RefPtr<Range> range = characterRangeAtPoint(frame, result.point());
     if (!range)
         return;
 
     uint64_t length;
-    getLocationAndLengthFromRange(range, index, length);
+    getLocationAndLengthFromRange(range.get(), index, length);
 }
 
 static PassRefPtr<Range> convertToRange(Frame* frame, NSRange nsrange)
@@ -241,6 +242,84 @@ void WebPage::firstRectForCharacterRange(uint64_t location, uint64_t length, Web
     resultRect = frame->view()->contentsToWindow(rect);
 }
 
+void WebPage::performDictionaryLookupAtLocation(const FloatPoint& floatPoint)
+{
+    Frame* frame = m_page->mainFrame();
+    if (!frame)
+        return;
+
+    // Find the frame the point is over.
+    IntPoint point = roundedIntPoint(floatPoint);
+
+    HitTestResult result = frame->eventHandler()->hitTestResultAtPoint(point, false);
+    frame = result.innerNonSharedNode() ? result.innerNonSharedNode()->document()->frame() : m_page->focusController()->focusedOrMainFrame();
+
+    // Figure out if there are any characters under the point.
+    RefPtr<Range> characterRange = characterRangeAtPoint(frame, frame->view()->windowToContents(point));
+    if (!characterRange)
+        return;
+
+    // Grab the currently selected text.
+    RefPtr<Range> selectedRange = m_page->focusController()->focusedOrMainFrame()->selection()->selection().toNormalizedRange();
+
+    // Use the selected text if the point was anywhere in it. Assertain this by seeing if either character range
+    // the mouse is over is contained by the selection range.
+    if (characterRange && selectedRange) {
+        ExceptionCode ec = 0;
+        selectedRange->compareBoundaryPoints(Range::START_TO_START, characterRange.get(), ec);
+        if (!ec) {
+            if (selectedRange->isPointInRange(characterRange->startContainer(), characterRange->startOffset(), ec)) {
+                if (!ec)
+                    characterRange = selectedRange;
+            }
+        }
+    }
+
+    if (!characterRange)
+        return;
+
+    // Ensure we have whole words.
+    VisibleSelection selection(characterRange.get());
+    selection.expandUsingGranularity(WordGranularity);
+
+    RefPtr<Range> finalRange = selection.toNormalizedRange();
+    if (!finalRange)
+        return;
+
+    performDictionaryLookupForRange(DictionaryPopupInfo::HotKey, frame, finalRange.get());
+}
+
+void WebPage::performDictionaryLookupForRange(DictionaryPopupInfo::Type type, Frame* frame, Range* range)
+{
+    String rangeText = range->text();
+    if (rangeText.stripWhiteSpace().isEmpty())
+        return;
+    
+    RenderObject* renderer = range->startContainer()->renderer();
+    RenderStyle* style = renderer->style();
+    NSFont *font = style->font().primaryFont()->getNSFont();
+    if (!font)
+        return;
+    
+    CFDictionaryRef fontDescriptorAttributes = (CFDictionaryRef)[[font fontDescriptor] fontAttributes];
+    if (!fontDescriptorAttributes)
+        return;
+
+    Vector<FloatQuad> quads;
+    range->textQuads(quads);
+    if (quads.isEmpty())
+        return;
+    
+    IntRect rangeRect = frame->view()->contentsToWindow(quads[0].enclosingBoundingBox());
+    
+    DictionaryPopupInfo dictionaryPopupInfo;
+    dictionaryPopupInfo.type = type;
+    dictionaryPopupInfo.origin = FloatPoint(rangeRect.x(), rangeRect.y());
+    dictionaryPopupInfo.fontInfo.fontAttributeDictionary = fontDescriptorAttributes;
+
+    send(Messages::WebPageProxy::DidPerformDictionaryLookup(rangeText, dictionaryPopupInfo));
+}
+
 static inline void scroll(Page* page, ScrollDirection direction, ScrollGranularity granularity)
 {
     page->focusController()->focusedOrMainFrame()->eventHandler()->scrollRecursively(direction, granularity);
@@ -349,6 +428,13 @@ void WebPage::registerUIProcessAccessibilityTokens(const CoreIPC::DataReference&
 #endif
 }
 
+void WebPage::writeSelectionToPasteboard(const String& pasteboardName, const Vector<String>& pasteboardTypes, bool& result)
+{
+    Frame* frame = m_page->focusController()->focusedOrMainFrame();
+    frame->editor()->writeSelectionToPasteboard(pasteboardName, pasteboardTypes);
+    result = true;
+}
+
 AccessibilityWebPageObject* WebPage::accessibilityRemoteObject()
 {
     return m_mockAccessibilityElement.get();
@@ -358,7 +444,13 @@ bool WebPage::platformHasLocalDataForURL(const WebCore::KURL& url)
 {
     NSMutableURLRequest* request = [[NSMutableURLRequest alloc] initWithURL:url];
     [request setValue:(NSString*)userAgent() forHTTPHeaderField:@"User-Agent"];
-    NSCachedURLResponse *cachedResponse = [[NSURLCache sharedURLCache] cachedResponseForRequest:request];
+    NSCachedURLResponse *cachedResponse;
+#if USE(CFURLSTORAGESESSIONS)
+    if (CFURLStorageSessionRef storageSession = ResourceHandle::privateBrowsingStorageSession())
+        cachedResponse = WKCachedResponseForRequest(storageSession, request);
+    else
+#endif
+        cachedResponse = [[NSURLCache sharedURLCache] cachedResponseForRequest:request];
     [request release];
     
     return cachedResponse;
@@ -368,7 +460,13 @@ String WebPage::cachedResponseMIMETypeForURL(const WebCore::KURL& url)
 {
     NSMutableURLRequest* request = [[NSMutableURLRequest alloc] initWithURL:url];
     [request setValue:(NSString*)userAgent() forHTTPHeaderField:@"User-Agent"];
-    NSCachedURLResponse *cachedResponse = [[NSURLCache sharedURLCache] cachedResponseForRequest:request];
+    NSCachedURLResponse *cachedResponse;
+#if USE(CFURLSTORAGESESSIONS)
+    if (CFURLStorageSessionRef storageSession = ResourceHandle::privateBrowsingStorageSession())
+        cachedResponse = WKCachedResponseForRequest(storageSession, request);
+    else
+#endif
+        cachedResponse = [[NSURLCache sharedURLCache] cachedResponseForRequest:request];
     [request release];
     
     return [[cachedResponse response] MIMEType];
diff --git a/Source/WebKit2/WebProcess/WebPage/qt/WebInspectorQt.cpp b/Source/WebKit2/WebProcess/WebPage/qt/WebInspectorQt.cpp
index 1675d77..1a3b598 100644
--- a/Source/WebKit2/WebProcess/WebPage/qt/WebInspectorQt.cpp
+++ b/Source/WebKit2/WebProcess/WebPage/qt/WebInspectorQt.cpp
@@ -28,11 +28,9 @@
 
 #if ENABLE(INSPECTOR)
 
+#include <WebCore/NotImplemented.h>
 #include <wtf/text/WTFString.h>
 
-#define DISABLE_NOT_IMPLEMENTED_WARNINGS 1
-#include "NotImplemented.h"
-
 namespace WebKit {
 
 String WebInspector::localizedStringsURL() const
diff --git a/Source/WebKit2/WebProcess/WebPage/win/LayerBackedDrawingAreaWin.cpp b/Source/WebKit2/WebProcess/WebPage/win/LayerBackedDrawingAreaWin.cpp
deleted file mode 100644
index 3c2f3c9..0000000
--- a/Source/WebKit2/WebProcess/WebPage/win/LayerBackedDrawingAreaWin.cpp
+++ /dev/null
@@ -1,65 +0,0 @@
-/*
- * Copyright (C) 2010 Apple Inc. All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- * 1. Redistributions of source code must retain the above copyright
- *    notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- *    notice, this list of conditions and the following disclaimer in the
- *    documentation and/or other materials provided with the distribution.
- *
- * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
- * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
- * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
- * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
- * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
- * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
- * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
- * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
- * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
- * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
- * THE POSSIBILITY OF SUCH DAMAGE.
- */
-
-#include "config.h"
-#include "LayerBackedDrawingArea.h"
-
-#if USE(ACCELERATED_COMPOSITING)
-
-using namespace WebCore;
-
-namespace WebKit {
-
-void LayerBackedDrawingArea::platformInit()
-{
-}
-
-void LayerBackedDrawingArea::platformClear()
-{
-}
-
-void LayerBackedDrawingArea::attachCompositingContext()
-{
-}
-
-void LayerBackedDrawingArea::detachCompositingContext()
-{
-}
-
-void LayerBackedDrawingArea::setRootCompositingLayer(WebCore::GraphicsLayer* layer)
-{
-}
-
-void LayerBackedDrawingArea::scheduleCompositingLayerSync()
-{
-}
-
-void LayerBackedDrawingArea::syncCompositingLayers()
-{
-}
-
-} // namespace WebKit
-
-#endif // USE(ACCELERATED_COMPOSITING)
diff --git a/Source/WebKit2/WebProcess/WebPage/win/WebInspectorWin.cpp b/Source/WebKit2/WebProcess/WebPage/win/WebInspectorWin.cpp
index 3ae0dae..5ada45d 100644
--- a/Source/WebKit2/WebProcess/WebPage/win/WebInspectorWin.cpp
+++ b/Source/WebKit2/WebProcess/WebPage/win/WebInspectorWin.cpp
@@ -28,6 +28,7 @@
 
 #if ENABLE(INSPECTOR)
 
+#include "WebKitBundle.h"
 #include <wtf/RetainPtr.h>
 #include <wtf/text/WTFString.h>
 
@@ -35,7 +36,7 @@ namespace WebKit {
 
 String WebInspector::localizedStringsURL() const
 {
-    RetainPtr<CFURLRef> localizedStringsURLRef(AdoptCF, CFBundleCopyResourceURL(CFBundleGetBundleWithIdentifier(CFSTR("com.apple.WebKit")), CFSTR("localizedStrings"), CFSTR("js"), 0));
+    RetainPtr<CFURLRef> localizedStringsURLRef(AdoptCF, CFBundleCopyResourceURL(webKitBundle(), CFSTR("localizedStrings"), CFSTR("js"), 0));
     if (!localizedStringsURLRef)
         return String();
 
diff --git a/Source/WebKit2/WebProcess/WebPage/win/WebPageWin.cpp b/Source/WebKit2/WebProcess/WebPage/win/WebPageWin.cpp
index e20af3a..73ba2b2 100644
--- a/Source/WebKit2/WebProcess/WebPage/win/WebPageWin.cpp
+++ b/Source/WebKit2/WebProcess/WebPage/win/WebPageWin.cpp
@@ -36,6 +36,7 @@
 #include <WebCore/KeyboardEvent.h>
 #include <WebCore/Page.h>
 #include <WebCore/PlatformKeyboardEvent.h>
+#include <WebCore/ResourceHandle.h>
 #include <WebCore/Settings.h>
 #if PLATFORM(CG)
 #include <WebKitSystemInterface/WebKitSystemInterface.h>
@@ -253,7 +254,13 @@ bool WebPage::platformHasLocalDataForURL(const WebCore::KURL& url)
     RetainPtr<CFStringRef> userAgent(AdoptCF, userAgent().createCFString());
     CFURLRequestSetHTTPHeaderFieldValue(request.get(), CFSTR("User-Agent"), userAgent.get());
 
-    RetainPtr<CFURLCacheRef> cache(AdoptCF, CFURLCacheCopySharedURLCache());
+    RetainPtr<CFURLCacheRef> cache;
+#if USE(CFURLSTORAGESESSIONS)
+    if (CFURLStorageSessionRef storageSession = ResourceHandle::privateBrowsingStorageSession())
+        cache.adoptCF(wkCopyURLCache(storageSession));
+    else
+#endif
+        cache.adoptCF(CFURLCacheCopySharedURLCache());
 
     RetainPtr<CFCachedURLResponseRef> response(AdoptCF, CFURLCacheCopyResponseForRequest(cache.get(), request.get()));    
     return response;
@@ -271,7 +278,13 @@ String WebPage::cachedResponseMIMETypeForURL(const WebCore::KURL& url)
     RetainPtr<CFStringRef> userAgent(AdoptCF, userAgent().createCFString());
     CFURLRequestSetHTTPHeaderFieldValue(request.get(), CFSTR("User-Agent"), userAgent.get());
 
-    RetainPtr<CFURLCacheRef> cache(AdoptCF, CFURLCacheCopySharedURLCache());
+    RetainPtr<CFURLCacheRef> cache;
+#if USE(CFURLSTORAGESESSIONS)
+    if (CFURLStorageSessionRef storageSession = ResourceHandle::privateBrowsingStorageSession())
+        cache.adoptCF(wkCopyURLCache(storageSession));
+    else
+#endif
+        cache.adoptCF(CFURLCacheCopySharedURLCache());
 
     RetainPtr<CFCachedURLResponseRef> cachedResponse(AdoptCF, CFURLCacheCopyResponseForRequest(cache.get(), request.get()));