Fix black background when locking with fullscreen window:

ui/compositor/test/compositor_test_support.cc

Index: ui/compositor/test/compositor_test_support.cc
diff --git a/ui/compositor/test/compositor_test_support.cc b/ui/compositor/test/compositor_test_support.cc
index 0ac26095adb34a20d55a0c7e577f1345523e6d39..a2b7a0ad76d0a6960fcaa6bcfdb9765f720d5309 100644
--- a/ui/compositor/test/compositor_test_support.cc
+++ b/ui/compositor/test/compositor_test_support.cc
@@ -6,10 +6,26 @@
 
 #include "base/compiler_specific.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebKit.h"
+#include "ui/compositor/layer_animator.h"
 #include "webkit/glue/webkitplatformsupport_impl.h"
 
 namespace ui {
 
+namespace test {
+
+// static
+scoped_ptr<AnimationContainerTestHelper> CreateLayerAnimatorHelperForTest() {
+  LayerAnimator::set_disable_animations_for_test(false);
+
+  scoped_ptr<AnimationContainerTestHelper> result;
+  result.reset(
+      new AnimationContainerTestHelper(
+          internal::GetLayerAnimationContainer()));
+  return result.Pass();
+}
+
+}  // namespace test
+
 class CompositorTestPlatformSupport:
     public NON_EXPORTED_BASE(webkit_glue::WebKitPlatformSupportImpl) {
  public: