Remove frame flattening from rendering code.

Source/core/rendering/RenderIFrame.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 18 matching lines @@
 #include "core/rendering/RenderFrameBase.h"
 
 namespace WebCore {
 
 class RenderView;
 
 class RenderIFrame FINAL : public RenderFrameBase {
 public:
     explicit RenderIFrame(Element*);
 
-    bool flattenFrame() const;
     bool isSeamless() const;
 
 private:
     virtual LayoutUnit minPreferredLogicalWidth() const OVERRIDE;
     virtual LayoutUnit maxPreferredLogicalWidth() const OVERRIDE;
 
     virtual bool shouldComputeSizeAsReplaced() const OVERRIDE;
     virtual bool isInlineBlockOrInlineTable() const OVERRIDE;
 
     virtual void layout() OVERRIDE;
@@ skipping 21 matching lines @@
     return static_cast<const RenderIFrame*>(object);
 }
 
 // This will catch anyone doing an unnecessary cast.
 void toRenderIFrame(const RenderIFrame*);
 
 
 } // namespace WebCore
 
 #endif // RenderIFrame_h