Standardize usage of virtual/override/final in chrome/browser/extensions/

chrome/browser/extensions/token_cache/token_cache_service.h

 // Copyright (c) 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 CHROME_BROWSER_EXTENSIONS_TOKEN_CACHE_TOKEN_CACHE_SERVICE_H_
 #define CHROME_BROWSER_EXTENSIONS_TOKEN_CACHE_TOKEN_CACHE_SERVICE_H_
 
 #include <map>
 #include <string>
 
 #include "base/basictypes.h"
 #include "base/compiler_specific.h"
 #include "base/time/time.h"
 #include "components/keyed_service/core/keyed_service.h"
 #include "components/signin/core/browser/signin_manager_base.h"
 
 class Profile;
 
 namespace extensions {
 
 // This class caches tokens for the current user.  It will clear tokens out
 // when the user logs out or after the specified timeout interval, or when
 // the instance of chrome shuts down.
 class TokenCacheService : public KeyedService,
                           public SigninManagerBase::Observer {
  public:
   explicit TokenCacheService(Profile* profile);
-  virtual ~TokenCacheService();
+  ~TokenCacheService() override;
 
   // Store a token for the currently logged in user. We will look it up later by
   // the name given here, and we will expire the token after the timeout.  For a
   // timeout of 0, we never expire the token.  After time_to_live expires, the
   // token will be expired.
   void StoreToken(const std::string& token_name, const std::string& token_value,
                   base::TimeDelta time_to_live);
 
   // Retrieve a token for the currently logged in user.  This returns an empty
   // string if the token was not found or timed out.
   std::string RetrieveToken(const std::string& token_name);
 
   // KeyedService:
-  virtual void Shutdown() override;
+  void Shutdown() override;
 
  private:
   friend class TokenCacheTest;
   FRIEND_TEST_ALL_PREFIXES(TokenCacheTest, SignoutTest);
 
   // SigninManagerBase::Observer:
-  virtual void GoogleSignedOut(const std::string& account_id,
-                               const std::string& username) override;
+  void GoogleSignedOut(const std::string& account_id,
+                       const std::string& username) override;
 
   struct TokenCacheData {
     std::string token;
     base::Time expiration_time;
   };
 
   // Map the token name (string) to token data.
   std::map<std::string, TokenCacheData> token_cache_;
   const Profile* const profile_;
 
   DISALLOW_COPY_AND_ASSIGN(TokenCacheService);
 };
 
 }  // namespace extensions
 
 #endif  // CHROME_BROWSER_EXTENSIONS_TOKEN_CACHE_TOKEN_CACHE_SERVICE_H_