Change base::TickClock to a ref counted class.

ash/system/chromeos/session/logout_confirmation_controller.h

 // Copyright 2014 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_SYSTEM_CHROMEOS_SESSION_LOGOUT_CONFIRMATION_CONTROLLER_H_
 #define ASH_SYSTEM_CHROMEOS_SESSION_LOGOUT_CONFIRMATION_CONTROLLER_H_
 
 #include "ash/ash_export.h"
 #include "ash/shell_observer.h"
 #include "base/basictypes.h"
@@ skipping 22 matching lines @@
   explicit LogoutConfirmationController(const base::Closure& logout_closure);
   virtual ~LogoutConfirmationController();
 
   base::TickClock* clock() const { return clock_.get(); }
 
   // Shows a LogoutConfirmationDialog. If a confirmation dialog is already being
   // shown, it is closed and a new one opened if |logout_time| is earlier than
   // the current dialog's |logout_time_|.
   void ConfirmLogout(base::TimeTicks logout_time);
 
-  void SetClockForTesting(scoped_ptr<base::TickClock> clock);
+  void SetClockForTesting(const scoped_refptr<base::TickClock>& clock);
 
   // ShellObserver:
   virtual void OnLockStateChanged(bool locked) override;
 
   // Called by the |dialog_| when the user confirms logout.
   void OnLogoutConfirmed();
 
   // Called by the |dialog_| when it is closed.
   void OnDialogClosed();
 
   LogoutConfirmationDialog* dialog_for_testing() const { return dialog_; }
 
  private:
-  scoped_ptr<base::TickClock> clock_;
+  scoped_refptr<base::TickClock> clock_;
   base::Closure logout_closure_;
 
   base::TimeTicks logout_time_;
   LogoutConfirmationDialog* dialog_;  // Owned by the Views hierarchy.
   base::Timer logout_timer_;
 
   DISALLOW_COPY_AND_ASSIGN(LogoutConfirmationController);
 };
 
 }  // namespace ash
 
 #endif  // ASH_SYSTEM_CHROMEOS_SESSION_LOGOUT_CONFIRMATION_CONTROLLER_H_