ash: Cleanup class/struct forward declarations

ash/wm/power_button_controller.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 ASH_WM_POWER_BUTTON_CONTROLLER_H_
 #define ASH_WM_POWER_BUTTON_CONTROLLER_H_
 
 #include <memory>
 
 #include "ash/ash_export.h"
 #include "base/macros.h"
 #include "base/time/time.h"
 #include "ui/events/event_handler.h"
 
 #if defined(OS_CHROMEOS)
 #include "chromeos/dbus/power_manager_client.h"
 #include "ui/display/chromeos/display_configurator.h"
 #endif
 
-namespace gfx {
-class Rect;
-class Size;
-}
-
-namespace ui {
-class Layer;
-}
-
 namespace ash {
 
 class LockStateController;
 #if defined(OS_CHROMEOS)
 class TabletPowerButtonController;
 #endif
 
 // Handles power & lock button events which may result in the locking or
 // shutting down of the system as well as taking screen shots while in maximize
 // mode.
@@ skipping 71 matching lines @@
   // Handles events for convertible/tablet devices.
   std::unique_ptr<TabletPowerButtonController> tablet_controller_;
 #endif
 
   DISALLOW_COPY_AND_ASSIGN(PowerButtonController);
 };
 
 }  // namespace ash
 
 #endif  // ASH_WM_POWER_BUTTON_CONTROLLER_H_