Make GL calls go through subclassable class.

ui/gl/gl_fence.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 "ui/gl/gl_fence.h"
 
 #include "base/compiler_specific.h"
 #include "ui/gl/gl_bindings.h"
 #include "ui/gl/gl_context.h"
 
@@ skipping 64 matching lines @@
 namespace gfx {
 
 GLFence::GLFence() {
 }
 
 GLFence::~GLFence() {
 }
 
 // static
 GLFence* GLFence::Create() {
-  if (gfx::g_GL_NV_fence) {
+  if (gfx::g_driver_gl.ext.b_GL_NV_fence) {
     return new GLFenceNVFence();
-  } else if (gfx::g_GL_ARB_sync) {
+  } else if (gfx::g_driver_gl.ext.b_GL_ARB_sync) {
     return new GLFenceARBSync();
   } else {
     return NULL;
   }
 }
 
 // static
 bool GLFence::IsContextLost() {
-  if (!gfx::g_GL_ARB_robustness && !gfx::g_GL_EXT_robustness)
+  if (!gfx::g_driver_gl.ext.b_GL_ARB_robustness &&
+      !gfx::g_driver_gl.ext.b_GL_EXT_robustness)
     return false;
 
   if (!gfx::GLContext::GetCurrent() ||
       !gfx::GLContext::GetCurrent()->
           WasAllocatedUsingRobustnessExtension())
     return false;
 
   GLenum status = glGetGraphicsResetStatusARB();
   return status != GL_NO_ERROR;
 }
 
 }  // namespace gfx