ash: Cleanup class/struct forward declarations

ash/common/wm/panels/panel_layout_manager.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_PANELS_PANEL_LAYOUT_MANAGER_H_
 #define ASH_COMMON_WM_PANELS_PANEL_LAYOUT_MANAGER_H_
 
 #include <list>
 #include <memory>
 
 #include "ash/ash_export.h"
 #include "ash/common/shelf/wm_shelf_observer.h"
 #include "ash/common/shell_observer.h"
 #include "ash/common/wm/window_state_observer.h"
 #include "ash/common/wm_activation_observer.h"
 #include "ash/common/wm_display_observer.h"
 #include "ash/common/wm_layout_manager.h"
 #include "ash/common/wm_window_observer.h"
 #include "ash/common/wm_window_tracker.h"
 #include "base/compiler_specific.h"
 #include "base/macros.h"
 #include "base/memory/weak_ptr.h"
 #include "ui/keyboard/keyboard_controller.h"
 #include "ui/keyboard/keyboard_controller_observer.h"
 
-namespace aura {
-class Window;
-}
-
 namespace gfx {
 class Rect;
 }
 
 namespace views {
 class Widget;
 }
 
 namespace ash {
 class PanelCalloutWidget;
-class ShelfLayoutManager;
 class WmShelf;
 
 namespace wm {
 class WmRootWindowController;
 }
 
 // PanelLayoutManager is responsible for organizing panels within the
 // workspace. It is associated with a specific container window (i.e.
 // kShellWindowId_PanelContainer) and controls the layout of any windows
 // added to that container.
@@ skipping 148 matching lines @@
   // are currently focused.
   WmWindow* last_active_panel_;
   base::WeakPtrFactory<PanelLayoutManager> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(PanelLayoutManager);
 };
 
 }  // namespace ash
 
 #endif  // ASH_COMMON_WM_PANELS_PANEL_LAYOUT_MANAGER_H_