Remove setErrorMessageCallback from WebGraphicsContext3D.

gpu/command_buffer/client/gles2_implementation.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_COMMAND_BUFFER_CLIENT_GLES2_IMPLEMENTATION_H_
 #define GPU_COMMAND_BUFFER_CLIENT_GLES2_IMPLEMENTATION_H_
 
 #include <stddef.h>
 #include <stdint.h>
 
@@ skipping 190 matching lines @@
   // ContextSupport implementation.
   void Swap() override;
   void PartialSwapBuffers(const gfx::Rect& sub_buffer) override;
   void CommitOverlayPlanes() override;
   void ScheduleOverlayPlane(int plane_z_order,
                             gfx::OverlayTransform plane_transform,
                             unsigned overlay_texture_id,
                             const gfx::Rect& display_bounds,
                             const gfx::RectF& uv_rect) override;
   uint64_t ShareGroupTracingGUID() const override;
+  void SetErrorMessageCallback(
+      const base::Callback<void(const char*, int32_t)>& callback) override;
 
-  void SetErrorMessageCallback(
-      const base::Callback<void(const char*, int32_t)>& callback);
+  // TODO(danakj): Move to ContextSupport once ContextProvider doesn't need to
+  // intercept it.
   void SetLostContextCallback(const base::Closure& callback);
 
   void GetProgramInfoCHROMIUMHelper(GLuint program,
                                     std::vector<int8_t>* result);
   GLint GetAttribLocationHelper(GLuint program, const char* name);
   GLint GetUniformLocationHelper(GLuint program, const char* name);
   GLint GetFragDataIndexEXTHelper(GLuint program, const char* name);
   GLint GetFragDataLocationHelper(GLuint program, const char* name);
   bool GetActiveAttribHelper(
       GLuint program, GLuint index, GLsizei bufsize, GLsizei* length,
@@ skipping 666 matching lines @@
 
 inline bool GLES2Implementation::GetTexParameterivHelper(
     GLenum /* target */, GLenum /* pname */, GLint* /* params */) {
   return false;
 }
 
 }  // namespace gles2
 }  // namespace gpu
 
 #endif  // GPU_COMMAND_BUFFER_CLIENT_GLES2_IMPLEMENTATION_H_