Refactor so chromium only GL extensions require gl2extchromium.h

gpu/command_buffer/tests/gl_texture_mailbox_unittests.cc

 // 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.
 
 #include <GLES2/gl2.h>
 #include <GLES2/gl2ext.h>
+#include <GLES2/gl2extchromium.h>
 
 #include "gpu/command_buffer/service/mailbox_manager.h"
 #include "gpu/command_buffer/tests/gl_manager.h"
 #include "testing/gmock/include/gmock/gmock.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "ui/gl/gl_share_group.h"
 
 namespace gpu {
 
 namespace {
@@ skipping 137 matching lines @@
   glConsumeTextureCHROMIUM(GL_TEXTURE_2D, invalid_mailbox);
   EXPECT_EQ(static_cast<GLenum>(GL_INVALID_OPERATION), glGetError());
 
   // Ensure level 0 is still intact after glConsumeTextureCHROMIUM fails.
   EXPECT_EQ(static_cast<GLenum>(GL_NO_ERROR), glGetError());
   EXPECT_EQ(source_pixel, ReadTexel(tex, 0, 0));
   EXPECT_EQ(static_cast<GLenum>(GL_NO_ERROR), glGetError());
 }
 }  // namespace gpu