Revert of Remove remote tree host and some related input and metro_driver code

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 22 matching lines @@
 #include "ui/gfx/geometry/point.h"
 #include "ui/gfx/screen.h"
 #include "ui/wm/core/coordinate_conversion.h"
 
 #if defined(OS_CHROMEOS)
 #include "ash/system/chromeos/tray_display.h"
 #endif
 
 #if defined(OS_WIN)
 #include "base/win/windows_version.h"
+#include "ui/aura/remote_window_tree_host_win.h"
 #include "ui/platform_window/win/win_window.h"
 #include "win8/test/test_registrar_constants.h"
 #endif
 
 #if defined(USE_X11)
 #include "ui/gfx/x/x11_connection.h"
 #endif
 
 namespace ash {
 namespace test {
@@ skipping 284 matching lines @@
 
 void AshTestBase::DisableIME() {
   Shell::GetInstance()->RemovePreTargetHandler(
       Shell::GetInstance()
           ->window_tree_host_manager()
           ->input_method_event_handler());
 }
 
 }  // namespace test
 }  // namespace ash