Make GL calls go through subclassable class.

content/common/gpu/gpu_channel_manager.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 "content/common/gpu/gpu_channel_manager.h"
 
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "content/common/child_thread.h"
 #include "content/common/gpu/gpu_channel.h"
@@ skipping 40 matching lines @@
   gpu_channels_.clear();
   if (default_offscreen_surface_.get()) {
     default_offscreen_surface_->Destroy();
     default_offscreen_surface_ = NULL;
   }
   DCHECK(image_operations_.empty());
 }
 
 gpu::gles2::ProgramCache* GpuChannelManager::program_cache() {
   if (!program_cache_.get() &&
-      (gfx::g_ARB_get_program_binary || gfx::g_OES_get_program_binary) &&
+      (gfx::g_driver_gl.ext.b_ARB_get_program_binary ||
+       gfx::g_driver_gl.ext.b_OES_get_program_binary) &&
       !CommandLine::ForCurrentProcess()->HasSwitch(
           switches::kDisableGpuProgramCache)) {
     program_cache_.reset(new gpu::gles2::MemoryProgramCache());
   }
   return program_cache_.get();
 }
 
 void GpuChannelManager::RemoveChannel(int client_id) {
   gpu_channels_.erase(client_id);
 }
@@ skipping 199 matching lines @@
 
 gfx::GLSurface* GpuChannelManager::GetDefaultOffscreenSurface() {
   if (!default_offscreen_surface_.get()) {
     default_offscreen_surface_ = gfx::GLSurface::CreateOffscreenGLSurface(
         false, gfx::Size(1, 1));
   }
   return default_offscreen_surface_.get();
 }
 
 }  // namespace content