Add infrastructure for partial layouts

Source/core/rendering/RenderFullScreen.h

 /*
  * 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
@@ skipping 29 matching lines @@
     void setPlaceholder(RenderBlock*);
     RenderBlock* placeholder() { return m_placeholder; }
     void createPlaceholder(PassRefPtr<RenderStyle>, const LayoutRect& frameRect);
 
 
     static RenderObject* wrapRenderer(RenderObject*, RenderObject*, Document*);
     void unwrapRenderer();
 
 private:
     RenderFullScreen();
+    virtual bool supportsPartialLayout() const OVERRIDE { return false; }
     virtual void willBeDestroyed();
 
 protected:
     RenderBlock* m_placeholder;
 };
 
 inline RenderFullScreen* toRenderFullScreen(RenderObject* object)
 {
     ASSERT_WITH_SECURITY_IMPLICATION(object->isRenderFullScreen());
     return static_cast<RenderFullScreen*>(object);
 }
 
 // This will catch anyone doing an unnecessary cast:
 void toRenderFullScreen(RenderFullScreen*);
 }
 
 #endif