replace 'virtual ... OVERRIDE' with '... override'

base/threading/watchdog.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.
 
 // The Watchdog class creates a second thread that can Alarm if a specific
 // duration of time passes without proper attention.  The duration of time is
 // specified at construction time.  The Watchdog may be used many times by
 // simply calling Arm() (to start timing) and Disarm() (to reset the timer).
 // The Watchdog is typically used under a debugger, where the stack traces on
 // other threads can be examined if/when the Watchdog alarms.
@@ skipping 47 matching lines @@
 
   // Reset static data to initial state. Useful for tests, to ensure
   // they are independent.
   static void ResetStaticData();
 
  private:
   class ThreadDelegate : public PlatformThread::Delegate {
    public:
     explicit ThreadDelegate(Watchdog* watchdog) : watchdog_(watchdog) {
     }
-    virtual void ThreadMain() OVERRIDE;
+    void ThreadMain() override;
+
    private:
     void SetThreadName() const;
 
     Watchdog* watchdog_;
   };
 
   enum State {ARMED, DISARMED, SHUTDOWN, JOINABLE };
 
   bool enabled_;
 
   Lock lock_;  // Mutex for state_.
   ConditionVariable condition_variable_;
   State state_;
   const TimeDelta duration_;  // How long after start_time_ do we alarm?
   const std::string thread_watched_name_;
   PlatformThreadHandle handle_;
   ThreadDelegate delegate_;  // Store it, because it must outlive the thread.
 
   TimeTicks start_time_;  // Start of epoch, and alarm after duration_.
 
   DISALLOW_COPY_AND_ASSIGN(Watchdog);
 };
 
 }  // namespace base
 
 #endif  // BASE_THREADING_WATCHDOG_H_