Remove linked_ptr from ash

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>
 
 #include "ash/ash_export.h"
 #include "ash/common/shell_observer.h"
 #include "ash/common/wm_window_observer.h"
 #include "base/compiler_specific.h"
 #include "base/macros.h"
-#include "base/memory/linked_ptr.h"
 #include "base/observer_list.h"
 #include "base/scoped_observer.h"
 #include "base/time/time.h"
 #include "base/timer/timer.h"
 #include "ui/aura/env_observer.h"
 #include "ui/aura/window_observer.h"
 
 namespace aura {
 class Window;
 }
@@ skipping 75 matching lines @@
   // ShellObserver overrides.
   void OnAppTerminating() override;
   void OnFullscreenStateChanged(bool is_fullscreen,
                                 WmWindow* root_window) override;
 
   // WmWindowObserver overrides.
   void OnWindowDestroyed(WmWindow* window) override {}
   void OnWindowDestroying(WmWindow* window) override;
 
  private:
-  class WindowInfo;
-  typedef std::map<aura::Window*, linked_ptr<WindowInfo>> WindowInfoMap;
-
   // 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.
   void UpdateState();
 
   // Current playback state.
   State state_;
 
   // True if video has been observed in the last |kVideoTimeoutMs|.
   bool video_is_playing_;
 
   // Currently-fullscreen root windows.
   std::set<WmWindow*> fullscreen_root_windows_;
 
   // Maps from a window that we're tracking to information about it.
+  class WindowInfo;
+  using WindowInfoMap = std::map<aura::Window*, std::unique_ptr<WindowInfo>>;
   WindowInfoMap window_infos_;
 
   base::ObserverList<Observer> observers_;
 
   // Calls HandleVideoInactive().
   base::OneShotTimer video_inactive_timer_;
 
   // If set, used when the current time is needed.  This can be set by tests to
   // simulate the passage of time.
   base::TimeTicks now_for_test_;
 
   ScopedObserver<aura::Window, aura::WindowObserver> window_observer_manager_;
   ScopedObserver<WmWindow, WmWindowObserver> wm_window_observer_manager_;
 
   bool is_shutting_down_;
 
   DISALLOW_COPY_AND_ASSIGN(VideoDetector);
 };
 
 }  // namespace ash
 
 #endif  // ASH_WM_VIDEO_DETECTOR_H_