Standardize usage of virtual/override/final specifiers.

ash/accelerators/key_hold_detector.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_ACCELERATOR_KEY_HOLD_DETECTOR_H_
 #define ASH_ACCELERATOR_KEY_HOLD_DETECTOR_H_
 
 #include "ash/ash_export.h"
 #include "base/memory/scoped_ptr.h"
 #include "ui/events/event_handler.h"
@@ skipping 21 matching lines @@
     virtual bool IsStartEvent(const ui::KeyEvent* event) const = 0;
 
     // Called when the key is held.
     virtual void OnKeyHold(const ui::KeyEvent* event) = 0;
 
     // Called when the key is release after hold.
     virtual void OnKeyUnhold(const ui::KeyEvent* event) = 0;
   };
 
   explicit KeyHoldDetector(scoped_ptr<Delegate> delegate);
-  virtual ~KeyHoldDetector();
+  ~KeyHoldDetector() override;
 
   // ui::EventHandler overrides:
-  virtual void OnKeyEvent(ui::KeyEvent* key_event) override;
+  void OnKeyEvent(ui::KeyEvent* key_event) override;
 
  private:
   // A state to keep track of one click and click and hold operation.
   //
   // One click:
   // INITIAL --(first press)--> PRESSED --(release)--> INITIAL[SEND PRESS]
   //
   // Click and hold:
   // INITIAL --(first press)--> PRESSED --(press)-->
   //   HOLD[OnKeyHold] --(press)--> HOLD[OnKeyHold] --(release)-->
   //   INITIAL[OnKeyUnhold]
   enum State {
     INITIAL,
     PRESSED,
     HOLD
   };
 
   State state_;
   scoped_ptr<Delegate> delegate_;
 
   DISALLOW_COPY_AND_ASSIGN(KeyHoldDetector);
 };
 
 }  // namespace ash
 
 #endif  // ASH_ACCELERATOR_KEY_HOLD_DETECTOR_H_