Third part of porting Chrome Ash to Windows 7

ash/test/ash_test_base.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 "ash/test/ash_test_base.h"
 
 #include <string>
 #include <vector>
 
 #include "ash/ash_switches.h"
@@ skipping 137 matching lines @@
   if (!command_line->HasSwitch(ash::switches::kForceAshToDesktop)) {
     if (base::win::GetVersion() >= base::win::VERSION_WIN8) {
       ipc_thread_.reset(new base::Thread("test_metro_viewer_ipc_thread"));
       base::Thread::Options options;
       options.message_loop_type = base::MessageLoop::TYPE_IO;
       ipc_thread_->StartWithOptions(options);
       metro_viewer_host_.reset(
           new TestMetroViewerProcessHost(ipc_thread_->message_loop_proxy()));
       CHECK(metro_viewer_host_->LaunchViewerAndWaitForConnection(
           win8::test::kDefaultTestAppUserModelId));
-      aura::RemoteWindowTreeHostWin* window_tree_host =
-          aura::RemoteWindowTreeHostWin::Instance();
-      CHECK(window_tree_host != NULL);
     }
     ash::WindowPositioner::SetMaximizeFirstWindow(true);
   }
 #endif
 }
 
 void AshTestBase::TearDown() {
   teardown_called_ = true;
   // Flush the message loop to finish pending release tasks.
   RunAllPendingInMessageLoop();
@@ skipping 181 matching lines @@
 
 void AshTestBase::UnblockUserSession() {
   Shell::GetInstance()->session_state_delegate()->UnlockScreen();
   SetSessionStarted(true);
   SetUserAddingScreenRunning(false);
 }
 
 
 }  // namespace test
 }  // namespace ash