Standardize usage of virtual/override/final in ui/

ui/gfx/animation/throb_animation.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 UI_GFX_ANIMATION_THROB_ANIMATION_H_
 #define UI_GFX_ANIMATION_THROB_ANIMATION_H_
 
 #include "ui/gfx/animation/slide_animation.h"
 
 namespace gfx {
 
 // A subclass of SlideAnimation that can continually slide. All of the Animation
 // methods behave like that of SlideAnimation: transition to the next state.
 // The StartThrobbing method causes the ThrobAnimation to cycle between hidden
 // and shown for a set number of cycles.
 //
 // A ThrobAnimation has two durations: the duration used when behavior like
 // a SlideAnimation, and the duration used when throbbing.
 class GFX_EXPORT ThrobAnimation : public SlideAnimation {
  public:
   explicit ThrobAnimation(AnimationDelegate* target);
-  virtual ~ThrobAnimation() {}
+  ~ThrobAnimation() override {}
 
   // Starts throbbing. cycles_til_stop gives the number of cycles to do before
   // stopping. A negative value means "throb indefinitely".
   void StartThrobbing(int cycles_til_stop);
 
   // Sets the duration of the slide animation when throbbing.
   void SetThrobDuration(int duration) { throb_duration_ = duration; }
 
   // Overridden to reset to the slide duration.
-  virtual void Reset() override;
-  virtual void Reset(double value) override;
-  virtual void Show() override;
-  virtual void Hide() override;
+  void Reset() override;
+  void Reset(double value) override;
+  void Show() override;
+  void Hide() override;
 
   // Overridden to maintain the slide duration.
-  virtual void SetSlideDuration(int duration) override;
+  void SetSlideDuration(int duration) override;
 
   // The number of cycles remaining until the animation stops.
   void set_cycles_remaining(int value) { cycles_remaining_ = value; }
   int cycles_remaining() const { return cycles_remaining_; }
 
  protected:
   // Overriden to continually throb (assuming we're throbbing).
-  virtual void Step(base::TimeTicks time_now) override;
+  void Step(base::TimeTicks time_now) override;
 
  private:
   // Resets state such that we behave like SlideAnimation.
   void ResetForSlide();
 
   // Duration of the slide animation.
   int slide_duration_;
 
   // Duration of the slide animation when throbbing.
   int throb_duration_;
 
   // If throbbing, this is the number of cycles left.
   int cycles_remaining_;
 
   // Are we throbbing?
   bool throbbing_;
 
   DISALLOW_COPY_AND_ASSIGN(ThrobAnimation);
 };
 
 }  // namespace gfx
 
 #endif  // UI_GFX_ANIMATION_THROB_ANIMATION_H_