Convert //ash from scoped_ptr to std::unique_ptr

ash/shell/window_watcher.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_SHELL_WINDOW_WATCHER_H_
 #define ASH_SHELL_WINDOW_WATCHER_H_
 
 #include <stdint.h>
 
 #include <map>
+#include <memory>
 
 #include "ash/shelf/shelf_item_types.h"
 #include "base/compiler_specific.h"
 #include "base/logging.h"
 #include "base/macros.h"
-#include "base/memory/scoped_ptr.h"
 #include "ui/aura/window_observer.h"
 #include "ui/gfx/display_observer.h"
 
 namespace aura {
 class Window;
 }
 
 namespace ash {
 namespace shell {
 
@@ skipping 20 matching lines @@
                                uint32_t metrics) override;
 
  private:
   class WorkspaceWindowWatcher;
 
   typedef std::map<ash::ShelfID, aura::Window*> IDToWindow;
 
   // Maps from window to the id we gave it.
   IDToWindow id_to_window_;
 
-  scoped_ptr<WorkspaceWindowWatcher> workspace_window_watcher_;
+  std::unique_ptr<WorkspaceWindowWatcher> workspace_window_watcher_;
 
   DISALLOW_COPY_AND_ASSIGN(WindowWatcher);
 };
 
 }  // namespace shell
 }  // namespace ash
 
 #endif  // ASH_SHELL_WINDOW_WATCHER_H_