Remove setErrorMessageCallback from WebGraphicsContext3D.

gpu/blink/webgraphicscontext3d_impl.h

 // Copyright (c) 2012 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 GPU_BLINK_WEBGRAPHICSCONTEXT3D_IMPL_H_
 #define GPU_BLINK_WEBGRAPHICSCONTEXT3D_IMPL_H_
 
 #include <stdint.h>
 
 #include <string>
 #include <vector>
 
 #include "base/callback.h"
 #include "base/memory/scoped_ptr.h"
 #include "gpu/blink/gpu_blink_export.h"
 #include "third_party/WebKit/public/platform/WebGraphicsContext3D.h"
 #include "third_party/WebKit/public/platform/WebString.h"
 
 namespace gpu {
 
 namespace gles2 {
 class GLES2Interface;
-class GLES2ImplementationErrorMessageCallback;
 struct ContextCreationAttribHelper;
 }
 }
 
 namespace gpu_blink {
 
-class WebGraphicsContext3DErrorMessageCallback;
-
 class GPU_BLINK_EXPORT WebGraphicsContext3DImpl
     : public NON_EXPORTED_BASE(blink::WebGraphicsContext3D) {
  public:
   ~WebGraphicsContext3DImpl() override;
 
   //----------------------------------------------------------------------
   // WebGraphicsContext3D methods
 
   void setContextLostCallback(
       WebGraphicsContext3D::WebGraphicsContextLostCallback* callback);
 
-  void setErrorMessageCallback(
-      WebGraphicsContext3D::WebGraphicsErrorMessageCallback* callback) override;
-
   ::gpu::gles2::GLES2Interface* GetGLInterface() {
     return gl_;
   }
 
  protected:
-  friend class WebGraphicsContext3DErrorMessageCallback;
-
   WebGraphicsContext3DImpl();
 
   void SetGLInterface(::gpu::gles2::GLES2Interface* gl) { gl_ = gl; }
 
   bool initialized_;
   bool initialize_failed_;
 
   WebGraphicsContextLostCallback* context_lost_callback_;
-  WebGraphicsErrorMessageCallback* error_message_callback_;
 
   ::gpu::gles2::GLES2Interface* gl_;
   bool lose_context_when_out_of_memory_;
 };
 
 }  // namespace gpu_blink
 
 #endif  // GPU_BLINK_WEBGRAPHICSCONTEXT3D_IMPL_H_