ash: Cleanup class/struct forward declarations

ash/common/wm/wm_toplevel_window_event_handler.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_COMMON_WM_WM_TOPLEVEL_WINDOW_EVENT_HANDLER_H_
 #define ASH_COMMON_WM_WM_TOPLEVEL_WINDOW_EVENT_HANDLER_H_
 
 #include <memory>
 
 #include "ash/ash_export.h"
 #include "ash/common/wm/wm_types.h"
 #include "ash/common/wm_display_observer.h"
 #include "base/callback.h"
 #include "base/macros.h"
 #include "ui/gfx/geometry/rect.h"
 #include "ui/wm/public/window_move_client.h"
 
 namespace ui {
 class KeyEvent;
 class LocatedEvent;
 class MouseEvent;
 class GestureEvent;
 }
 
 namespace ash {
 
-class WindowResizer;
 class WmShell;
 class WmWindow;
 
 namespace wm {
 
 // WmToplevelWindowEventHandler handles dragging and resizing of top level
 // windows. WmToplevelWindowEventHandler is forwarded events, such as from an
 // EventHandler.
 class ASH_EXPORT WmToplevelWindowEventHandler : public WmDisplayObserver {
  public:
@@ skipping 82 matching lines @@
 
   EndClosure end_closure_;
 
   DISALLOW_COPY_AND_ASSIGN(WmToplevelWindowEventHandler);
 };
 
 }  // namespace wm
 }  // namespace ash
 
 #endif  // ASH_COMMON_WM_WM_TOPLEVEL_WINDOW_EVENT_HANDLER_H_