Standardize usage of virtual/override/final in ui/

ui/app_list/search/history.h

 // Copyright 2013 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_SEARCH_HISTORY_H_
 #define UI_APP_LIST_SEARCH_HISTORY_H_
 
 #include <map>
 #include <string>
 
@@ skipping 17 matching lines @@
 // History tracks the launch events of the search results and uses HistoryData
 // to build user learning data out of these events. The learning data is stored
 // as associations between user typed query and launched result id. There are
 // primary and secondary associations. See HistoryData comments to see how
 // they are built. The learning data is sent to the mixer to boost results that
 // have been launched before.
 class APP_LIST_EXPORT History : public KeyedService,
                                 public HistoryDataObserver {
  public:
   explicit History(scoped_refptr<HistoryDataStore> store);
-  virtual ~History();
+  ~History() override;
 
   // Returns true if the service is ready.
   bool IsReady() const;
 
   // Adds a launch event to the learning data.
   void AddLaunchEvent(const std::string& query, const std::string& result_id);
 
   // Gets all known search results that were launched using the given |query|
   // or using queries that |query| is a prefix of.
   scoped_ptr<KnownResults> GetKnownResults(const std::string& query) const;
 
  private:
   friend class app_list::test::SearchHistoryTest;
 
   // HistoryDataObserver overrides:
-  virtual void OnHistoryDataLoadedFromStore() override;
+  void OnHistoryDataLoadedFromStore() override;
 
   scoped_ptr<HistoryData> data_;
   scoped_refptr<HistoryDataStore> store_;
   bool data_loaded_;
 
   DISALLOW_COPY_AND_ASSIGN(History);
 };
 
 }  // namespace app_list
 
 #endif  // UI_APP_LIST_SEARCH_HISTORY_H_