Rework composited scrolling updates.

Source/WebCore/page/FrameView.h

 /*
    Copyright (C) 1997 Martin Jones (mjones@kde.org)
              (C) 1998 Waldo Bastian (bastian@kde.org)
              (C) 1998, 1999 Torben Weis (weis@kde.org)
              (C) 1999 Lars Knoll (knoll@kde.org)
              (C) 1999 Antti Koivisto (koivisto@kde.org)
    Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009 Apple Inc. All rights reserved.
 
    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Library General Public
@@ skipping 98 matching lines @@
 
     bool needsLayout() const;
     void setNeedsLayout();
     void setViewportConstrainedObjectsNeedLayout();
 
     bool needsFullRepaint() const { return m_doFullRepaint; }
 
     void serviceScriptedAnimations(double monotonicAnimationStartTime);
 
     void updateCompositingLayersAfterStyleChange();
+    void updateCompositingLayersAfterLayoutAndPositioning();
     void updateCompositingLayersAfterLayout();
 
     bool hasCompositedContent() const;
     bool isEnclosedInCompositingLayer() const;
 
     // Returns true when a paint with the PaintBehaviorFlattenCompositingLayers flag set gives
     // a faithful representation of the content.
     bool isSoftwareRenderable() const;
 
     void didMoveOnscreen();
@@ skipping 477 matching lines @@
     ASSERT(!widget || widget->isFrameView());
     return static_cast<const FrameView*>(widget);
 }
 
 // This will catch anyone doing an unnecessary cast.
 void toFrameView(const FrameView*);
 
 } // namespace WebCore
 
 #endif // FrameView_h