[mus+ash] Removes WmWindow from screen_dimmer and video_detector

ash/wm/video_detector.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_VIDEO_DETECTOR_H_
 #define ASH_WM_VIDEO_DETECTOR_H_
 
 #include <map>
 #include <memory>
 #include <set>
@@ skipping 86 matching lines @@
   void OnDelegatedFrameDamage(aura::Window* window,
                               const gfx::Rect& region) override;
   void OnWindowDestroyed(aura::Window* window) override;
   void OnWindowDestroying(aura::Window* window) override;
 
   // SessionStateController overrides.
   void OnChromeTerminating() override;
 
   // ShellObserver overrides.
   void OnFullscreenStateChanged(bool is_fullscreen,
-                                WmWindow* root_window) override;
+                                aura::Window* root_window) override;
 
  private:
   // Called when video activity is observed in |window|.
   void HandleVideoActivity(aura::Window* window, base::TimeTicks now);
 
   // Called by |inactive_timer_| |kVideoTimeoutMs| after the last-observed video
   // activity.
   void HandleVideoInactive();
 
   // Updates |state_| and notifies |observers_| if it changed.
@@ skipping 26 matching lines @@
   ScopedSessionObserver scoped_session_observer_;
 
   bool is_shutting_down_;
 
   DISALLOW_COPY_AND_ASSIGN(VideoDetector);
 };
 
 }  // namespace ash
 
 #endif  // ASH_WM_VIDEO_DETECTOR_H_