ui: Allow individual test suites to opt-out of the TestCompositor.

ui/gl/gl_implementation.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_implementation.h"
 
 #include <algorithm>
 #include <string>
 
 #include "base/at_exit.h"
@@ skipping 131 matching lines @@
 
   return NULL;
 }
 
 void InitializeNullDrawGLBindings() {
   // This is platform independent, so it does not need to live in a platform
   // specific implementation file.
   InitializeNullDrawGLBindingsGL();
 }
 
+bool HasInitializedNullDrawGLBindings() {
+  return HasInitializedNullDrawGLBindingsGL();
+}
+
 DisableNullDrawGLBindings::DisableNullDrawGLBindings() {
   initial_enabled_ = SetNullDrawGLBindingsEnabledGL(false);
 }
 
 DisableNullDrawGLBindings::~DisableNullDrawGLBindings() {
   SetNullDrawGLBindingsEnabledGL(initial_enabled_);
 }
 
 }  // namespace gfx