Implement WEBGL_shared_resources

Source/core/html/canvas/WebGLRenderbuffer.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 54 matching lines @@
     WebGLRenderbuffer* emulatedStencilBuffer() const { return m_emulatedStencilBuffer.get(); }
     void deleteEmulatedStencilBuffer(GraphicsContext3D* context3d);
 
 protected:
     WebGLRenderbuffer(WebGLRenderingContext*);
 
     virtual void deleteObjectImpl(GraphicsContext3D*, Platform3DObject);
 
 private:
     virtual bool isRenderbuffer() const { return true; }
+    virtual const char* typeName() const { return "WebGLRenderuffer"; }
 
     GC3Denum m_internalFormat;
     bool m_initialized;
     GC3Dsizei m_width, m_height;
 
     bool m_hasEverBeenBound;
 
     RefPtr<WebGLRenderbuffer> m_emulatedStencilBuffer;
 };
 
 } // namespace WebCore
 
 #endif // WebGLRenderbuffer_h