[Oilpan] Migrate classes under module/webgl onto oilpan heap

Source/modules/webgl/CHROMIUMValuebuffer.h

 // Copyright (c) 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CHROMIUMValuebuffer_h
 #define CHROMIUMValuebuffer_h
 
 #include "modules/webgl/WebGLSharedPlatform3DObject.h"
-#include "wtf/PassRefPtr.h"
 
 namespace blink {
 
 class CHROMIUMValuebuffer final : public WebGLSharedPlatform3DObject {
     DEFINE_WRAPPERTYPEINFO();
 public:
     ~CHROMIUMValuebuffer() override;
 
-    static PassRefPtrWillBeRawPtr<CHROMIUMValuebuffer> create(WebGLRenderingContextBase*);
+    static CHROMIUMValuebuffer* create(WebGLRenderingContextBase*);
 
     bool hasEverBeenBound() const { return m_hasEverBeenBound; }
 
     void setHasEverBeenBound() { m_hasEverBeenBound = true; }
 
 protected:
     explicit CHROMIUMValuebuffer(WebGLRenderingContextBase*);
 
     void deleteObjectImpl(WebGraphicsContext3D*) override;
 
 private:
 
     bool m_hasEverBeenBound;
 };
 
 } // namespace blink
 
 #endif // CHROMIUMValuebuffer_h