Oilpan: move 2D Canvas and WebGL objects to the heap.

Source/core/html/canvas/WebGLContextObject.h

 /*
  * Copyright (C) 2011 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 17 matching lines @@
 
 #include "core/html/canvas/WebGLObject.h"
 
 namespace blink {
 class WebGraphicsContext3D;
 }
 
 namespace blink {
 
 class WebGLRenderingContextBase;
+class WebGLSharedWebGraphicsContext3D;
 
 // WebGLContextObject the base class for objects that are owned by a specific
 // WebGLRenderingContextBase.
 class WebGLContextObject : public WebGLObject {
 public:
     virtual ~WebGLContextObject();
 
     WebGLRenderingContextBase* context() const { return m_context; }
 
     virtual bool validate(const WebGLContextGroup*, const WebGLRenderingContextBase* context) const OVERRIDE FINAL
     {
         return context == m_context;
     }
 
     void detachContext();
 
+    virtual void trace(Visitor*) OVERRIDE;
+
 protected:
-    WebGLContextObject(WebGLRenderingContextBase*);
+    explicit WebGLContextObject(WebGLRenderingContextBase*);
 
     virtual bool hasGroupOrContext() const OVERRIDE FINAL
     {
         return m_context;
     }
 
     virtual blink::WebGraphicsContext3D* getAWebGraphicsContext3D() const OVERRIDE FINAL;
 
 private:
-    WebGLRenderingContextBase* m_context;
+    RawPtrWillBeMember<WebGLRenderingContextBase> m_context;
+#if ENABLE(OILPAN)
+    RefPtr<WebGLSharedWebGraphicsContext3D> m_sharedWebGraphicsContext3D;
+#endif
 };
 
 } // namespace blink
 
 #endif // WebGLContextObject_h