Fix black background when locking with fullscreen window:

ui/compositor/test/compositor_test_support.h

 // 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.
 
 #ifndef UI_COMPOSITOR_TEST_COMPOSITOR_TEST_SUPPORT_H_
 #define UI_COMPOSITOR_TEST_COMPOSITOR_TEST_SUPPORT_H_
 
+#include "base/memory/scoped_ptr.h"
+#include "ui/base/animation/animation_container_test_helper.h"
+
 namespace ui {
 
+namespace test {
+
+scoped_ptr<AnimationContainerTestHelper> CreateLayerAnimatorHelperForTest();
+
+}
+
 class CompositorTestSupport {
  public:
   // Called by programs that want to use a real compositor,
   // but skip the typical initialization of browser_main.cc.
   static void Initialize();
   static void Terminate();
 };
 
 }  // namespace ui
 
 #endif  // UI_COMPOSITOR_TEST_COMPOSITOR_TEST_SUPPORT_H_