Convert //ash from scoped_ptr to std::unique_ptr

ash/wm/mru_window_tracker.h

 // Copyright 2013 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_MRU_WINDOW_TRACKER_H_
 #define ASH_WM_MRU_WINDOW_TRACKER_H_
 
 #include <list>
 #include <vector>
 
 #include "ash/ash_export.h"
 #include "base/macros.h"
-#include "base/memory/scoped_ptr.h"
 #include "ui/aura/window_observer.h"
 #include "ui/wm/public/activation_change_observer.h"
 
 namespace aura {
 class RootWindow;
 class Window;
 namespace client {
 class ActivationClient;
 }
 }
@@ skipping 62 matching lines @@
   wm::AshFocusRules* focus_rules_;  // Not owned.
 
   bool ignore_window_activations_;
 
   DISALLOW_COPY_AND_ASSIGN(MruWindowTracker);
 };
 
 }  // namespace ash
 
 #endif  // ASH_WM_MRU_WINDOW_TRACKER_H_