Standardize usage of virtual/override/final specifiers.

ui/app_list/views/tile_item_view.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 UI_APP_LIST_VIEWS_TILE_ITEM_VIEW_H_
 #define UI_APP_LIST_VIEWS_TILE_ITEM_VIEW_H_
 
 #include "ui/app_list/app_list_export.h"
 #include "ui/app_list/search_result_observer.h"
 #include "ui/views/controls/button/button.h"
 #include "ui/views/controls/button/custom_button.h"
 
 namespace views {
 class ImageView;
 class Label;
 }
 
 namespace app_list {
 
 class SearchResult;
 
 // The view for a tile in the app list on the start/search page.
 class APP_LIST_EXPORT TileItemView : public views::CustomButton,
                                      public views::ButtonListener,
                                      public SearchResultObserver {
  public:
   TileItemView();
-  virtual ~TileItemView();
+  ~TileItemView() override;
 
   void SetSearchResult(SearchResult* item);
 
  private:
   // Overridden from views::View:
-  virtual gfx::Size GetPreferredSize() const override;
+  gfx::Size GetPreferredSize() const override;
 
   // Overridden from views::ButtonListener:
-  virtual void ButtonPressed(views::Button* sender,
-                             const ui::Event& event) override;
+  void ButtonPressed(views::Button* sender, const ui::Event& event) override;
 
   // Overridden from SearchResultObserver:
-  virtual void OnIconChanged() override;
-  virtual void OnResultDestroying() override;
+  void OnIconChanged() override;
+  void OnResultDestroying() override;
 
   // Owned by the model provided by the AppListViewDelegate.
   SearchResult* item_;
 
   views::ImageView* icon_;  // Owned by views hierarchy.
   views::Label* title_;     // Owned by views hierarchy.
 
   DISALLOW_COPY_AND_ASSIGN(TileItemView);
 };
 
 }  // namespace app_list
 
 #endif  // UI_APP_LIST_VIEWS_TILE_ITEM_VIEW_H_