Move flush id from WebGraphicsContext3DImpl to GLES2Implementation.

gpu/command_buffer/client/gles2_implementation_autogen.h

 // Copyright 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.
 
 // This file is auto-generated from
 // gpu/command_buffer/build_gles2_cmd_buffer.py
 // It's formatted by clang-format using chromium coding style:
 //    clang-format -i -style=chromium filename
 // DO NOT EDIT!
 
@@ skipping 1038 matching lines @@
                              const GLfloat* clip_rect,
                              GLint sorting_context_id,
                              const GLfloat* transform) override;
 
 void CommitOverlayPlanesCHROMIUM() override;
 
 void SwapInterval(GLint interval) override;
 
 void FlushDriverCachesCHROMIUM() override;
 
+GLuint GetLastFlushIdCHROMIUM() override;
+
 void MatrixLoadfCHROMIUM(GLenum matrixMode, const GLfloat* m) override;
 
 void MatrixLoadIdentityCHROMIUM(GLenum matrixMode) override;
 
 GLuint GenPathsCHROMIUM(GLsizei range) override;
 
 void DeletePathsCHROMIUM(GLuint path, GLsizei range) override;
 
 GLboolean IsPathCHROMIUM(GLuint path) override;
 
@@ skipping 117 matching lines @@
                              const char* name) override;
 
 GLint GetFragDataIndexEXT(GLuint program, const char* name) override;
 
 void UniformMatrix4fvStreamTextureMatrixCHROMIUM(
     GLint location,
     GLboolean transpose,
     const GLfloat* default_value) override;
 
 #endif  // GPU_COMMAND_BUFFER_CLIENT_GLES2_IMPLEMENTATION_AUTOGEN_H_