Add an API to report debugName in GraphicsLayer

Source/core/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 189 matching lines @@
     void resetTrackedRepaintRects();
     void setTracksRepaints(bool);
 
     void reportMemoryUsage(MemoryObjectInfo*) const;
     void setShouldReevaluateCompositingAfterLayout() { m_reevaluateCompositingAfterLayout = true; }
 
     bool viewHasTransparentBackground(Color* backgroundColor = 0) const;
 
     // Returns all reasons (direct, indirectly due to subtree, and indirectly due to overlap) that a layer should be composited.
     CompositingReasons reasonsForCompositing(const RenderLayer*) const;
+
+    virtual String debugName(const GraphicsLayer*) OVERRIDE;
     
 private:
     class OverlapMap;
 
     // GraphicsLayerClient implementation
     virtual void notifyAnimationStarted(const GraphicsLayer*, double) OVERRIDE { }
     virtual void paintContents(const GraphicsLayer*, GraphicsContext&, GraphicsLayerPaintingPhase, const IntRect&) OVERRIDE;
 
     virtual bool isTrackingRepaints() const OVERRIDE;
     
@@ skipping 144 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