replace OVERRIDE and FINAL with override and final in ash/

ash/system/chromeos/system_clock_observer.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_SYSTEM_CHROMEOS_SYSTEM_CLOCK_OBSERVER_H_
 #define ASH_SYSTEM_CHROMEOS_SYSTEM_CLOCK_OBSERVER_H_
 
 #include "chromeos/dbus/system_clock_client.h"
 #include "chromeos/settings/timezone_settings.h"
 
 namespace ash {
 
 class SystemClockObserver
     : public chromeos::SystemClockClient::Observer,
       public chromeos::system::TimezoneSettings::Observer {
  public:
   SystemClockObserver();
   virtual ~SystemClockObserver();
 
   // chromeos::SystemClockClient::Observer
-  virtual void SystemClockUpdated() OVERRIDE;
-  virtual void SystemClockCanSetTimeChanged(bool can_set_time) OVERRIDE;
+  virtual void SystemClockUpdated() override;
+  virtual void SystemClockCanSetTimeChanged(bool can_set_time) override;
 
   // chromeos::system::TimezoneSettings::Observer
-  virtual void TimezoneChanged(const icu::TimeZone& timezone) OVERRIDE;
+  virtual void TimezoneChanged(const icu::TimeZone& timezone) override;
 
   bool can_set_time() { return can_set_time_; }
 
  private:
   bool can_set_time_;
 
   DISALLOW_COPY_AND_ASSIGN(SystemClockObserver);
 };
 
 }  // namespace ash
 
 #endif  // ASH_SYSTEM_CHROMEOS_SYSTEM_CLOCK_OBSERVER_H_