Remove PlatformWidget references

Source/WebCore/rendering/RenderLayerCompositor.h

 /*
  * Copyright (C) 2009 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
@@ skipping 198 matching lines @@
     
 #if ENABLE(VIDEO)
     // Use by RenderVideo to ask if it should try to use accelerated compositing.
     bool canAccelerateVideoRendering(RenderVideo*) const;
 #endif
 
     // Walk the tree looking for layers with 3d transforms. Useful in case you need
     // to know if there is non-affine content, e.g. for drawing into an image.
     bool has3DContent() const;
     
-    // Most platforms connect compositing layer trees between iframes and their parent document.
-    // Some (currently just Mac) allow iframes to do their own compositing.
-    static bool allowsIndependentlyCompositedFrames(const FrameView*);
     bool shouldPropagateCompositingToEnclosingFrame() const;
 
     static RenderLayerCompositor* frameContentsCompositor(RenderPart*);
     // Return true if the layers changed.
     static bool parentFrameContentLayers(RenderPart*);
 
     // Update the geometry of the layers used for clipping and scrolling in frames.
     void frameViewDidChangeLocation(const IntPoint& contentsOffset);
     void frameViewDidChangeSize();
     void frameViewDidScroll();
@@ skipping 215 matching lines @@
     int m_secondaryCompositedLayerCount; // count of layers that have to be composited because of stacking or overlap.
     double m_obligatoryBackingStoreBytes;
     double m_secondaryBackingStoreBytes;
 #endif
 };
 
 
 } // namespace WebCore
 
 #endif // RenderLayerCompositor_h