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

Source/core/html/canvas/WebGLDrawBuffers.h

 /*
  * Copyright (C) 2013 Google 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
@@ skipping 16 matching lines @@
 #define WebGLDrawBuffers_h
 
 #include "bindings/core/v8/ScriptWrappable.h"
 #include "core/html/canvas/WebGLExtension.h"
 #include "wtf/PassRefPtr.h"
 
 namespace blink {
 
 class WebGLDrawBuffers FINAL : public WebGLExtension, public ScriptWrappable {
 public:
-    static PassRefPtr<WebGLDrawBuffers> create(WebGLRenderingContextBase*);
+    static PassRefPtrWillBeRawPtr<WebGLDrawBuffers> create(WebGLRenderingContextBase*);
     static bool supported(WebGLRenderingContextBase*);
     static const char* extensionName();
 
     virtual ~WebGLDrawBuffers();
     virtual WebGLExtensionName name() const OVERRIDE;
 
     void drawBuffersWEBGL(const Vector<GLenum>& buffers);
 
 private:
-    WebGLDrawBuffers(WebGLRenderingContextBase*);
+    explicit WebGLDrawBuffers(WebGLRenderingContextBase*);
 
     static bool satisfiesWebGLRequirements(WebGLRenderingContextBase*);
 };
 
 } // namespace blink
 
 #endif // WebGLDrawBuffers_h