Standardize usage of virtual/override/final specifiers.

ash/touch/touch_observer_hud.h

Index: ash/touch/touch_observer_hud.h
diff --git a/ash/touch/touch_observer_hud.h b/ash/touch/touch_observer_hud.h
index 329d7dc0281622db390e6d9b6274608b0732ca77..e168e9f814c99ccc8fdbcab5be2a32cc29bc8978 100644
--- a/ash/touch/touch_observer_hud.h
+++ b/ash/touch/touch_observer_hud.h
@@ -43,7 +43,7 @@ class ASH_EXPORT TouchObserverHUD : public ui::EventHandler,
  protected:
   explicit TouchObserverHUD(aura::Window* initial_root);
 
-  virtual ~TouchObserverHUD();
+  ~TouchObserverHUD() override;
 
   virtual void SetHudForRootWindowController(
       RootWindowController* controller) = 0;
@@ -53,16 +53,16 @@ class ASH_EXPORT TouchObserverHUD : public ui::EventHandler,
   views::Widget* widget() { return widget_; }
 
   // Overriden from ui::EventHandler.
-  virtual void OnTouchEvent(ui::TouchEvent* event) override;
+  void OnTouchEvent(ui::TouchEvent* event) override;
 
   // Overridden from views::WidgetObserver.
-  virtual void OnWidgetDestroying(views::Widget* widget) override;
+  void OnWidgetDestroying(views::Widget* widget) override;
 
   // Overridden from gfx::DisplayObserver.
-  virtual void OnDisplayAdded(const gfx::Display& new_display) override;
-  virtual void OnDisplayRemoved(const gfx::Display& old_display) override;
-  virtual void OnDisplayMetricsChanged(const gfx::Display& display,
-                                       uint32_t metrics) override;
+  void OnDisplayAdded(const gfx::Display& new_display) override;
+  void OnDisplayRemoved(const gfx::Display& old_display) override;
+  void OnDisplayMetricsChanged(const gfx::Display& display,
+                               uint32_t metrics) override;
 
 #if defined(OS_CHROMEOS)
   // Overriden from ui::DisplayConfigurator::Observer.
@@ -71,9 +71,9 @@ class ASH_EXPORT TouchObserverHUD : public ui::EventHandler,
 #endif  // defined(OS_CHROMEOS)
 
   // Overriden form DisplayController::Observer.
-  virtual void OnDisplaysInitialized() override;
-  virtual void OnDisplayConfigurationChanging() override;
-  virtual void OnDisplayConfigurationChanged() override;
+  void OnDisplaysInitialized() override;
+  void OnDisplayConfigurationChanging() override;
+  void OnDisplayConfigurationChanged() override;
 
  private:
   friend class TouchHudTestBase;