Use a mocked compositor for unit tests

ui/aura/test/aura_test_base.cc

 // Copyright (c) 2011 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/aura/test/aura_test_base.h"
 
 #if defined(OS_WIN)
 #include <ole2.h>
 #endif
 
 #include "ui/aura/desktop.h"
 #include "ui/aura/test/test_desktop_delegate.h"
 #include "ui/gfx/compositor/test_compositor.h"
 
 namespace aura {
 namespace test {
 
-static ui::Compositor* TestCreateCompositor() {
-  return new ui::TestCompositor();
+static ui::Compositor* TestCreateCompositor(ui::CompositorDelegate* owner) {
+  return new ui::TestCompositor(owner);
 }
 
 AuraTestBase::AuraTestBase()
     : setup_called_(false),
       teardown_called_(false) {
 #if defined(OS_WIN)
   OleInitialize(NULL);
 #endif
 }
 
@@ skipping 21 matching lines @@
   // Flush the message loop because we have pending release tasks
   // and these tasks if un-executed would upset Valgrind.
   RunPendingMessages();
   teardown_called_ = true;
   testing::Test::TearDown();
   aura::Desktop::set_compositor_factory_for_testing(NULL);
 }
 
 }  // namespace test
 }  // namespace aura