[mus+ash] Removes WmWindow from ash/wm/mru_window_tracker and overview mode

ash/wm/overview/scoped_overview_animation_settings_factory.h

 // Copyright 2016 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_OVERVIEW_SCOPED_OVERVIEW_ANIMATION_SETTINGS_FACTORY_H_
 #define ASH_WM_OVERVIEW_SCOPED_OVERVIEW_ANIMATION_SETTINGS_FACTORY_H_
 
 #include <memory>
 
 #include "ash/wm/overview/overview_animation_type.h"
 
+namespace aura {
+class Window;
+}
+
 namespace ash {
 
 class ScopedOverviewAnimationSettings;
-class WmWindow;
 
 // Factory for creating ScopedOverviewAnimationSettings.
 class ScopedOverviewAnimationSettingsFactory {
  public:
   static ScopedOverviewAnimationSettingsFactory* Get();
 
   virtual std::unique_ptr<ScopedOverviewAnimationSettings>
   CreateOverviewAnimationSettings(OverviewAnimationType animation_type,
-                                  WmWindow* window) = 0;
+                                  aura::Window* window) = 0;
 
  protected:
   ScopedOverviewAnimationSettingsFactory();
   virtual ~ScopedOverviewAnimationSettingsFactory();
 
  private:
   static ScopedOverviewAnimationSettingsFactory* instance_;
 };
 
 }  // namespace ash
 
 #endif  // ASH_WM_OVERVIEW_SCOPED_OVERVIEW_ANIMATION_SETTINGS_FACTORY_H_