Update {virtual,override,final} to follow C++11 style.

chrome/browser/signin/android_profile_oauth2_token_service.cc

 // 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.
 
 #include "chrome/browser/signin/android_profile_oauth2_token_service.h"
 
 #include "base/android/jni_android.h"
 #include "base/android/jni_array.h"
 #include "base/android/jni_string.h"
 #include "base/bind.h"
@@ skipping 21 matching lines @@
 // - the expiry time of the token (may be null, indicating that the expiry
 //   time is unknown.
 typedef base::Callback<void(
     const GoogleServiceAuthError&, const std::string&, const base::Time&)>
         FetchOAuth2TokenCallback;
 
 class AndroidAccessTokenFetcher : public OAuth2AccessTokenFetcher {
  public:
   AndroidAccessTokenFetcher(OAuth2AccessTokenConsumer* consumer,
                             const std::string& account_id);
-  virtual ~AndroidAccessTokenFetcher();
+  ~AndroidAccessTokenFetcher() override;
 
   // Overrides from OAuth2AccessTokenFetcher:
-  virtual void Start(const std::string& client_id,
-                     const std::string& client_secret,
-                     const std::vector<std::string>& scopes) override;
-  virtual void CancelRequest() override;
+  void Start(const std::string& client_id,
+             const std::string& client_secret,
+             const std::vector<std::string>& scopes) override;
+  void CancelRequest() override;
 
   // Handles an access token response.
   void OnAccessTokenResponse(const GoogleServiceAuthError& error,
                              const std::string& access_token,
                              const base::Time& expiration_time);
 
  private:
   std::string CombineScopes(const std::vector<std::string>& scopes);
 
   std::string account_id_;
@@ skipping 410 matching lines @@
   GoogleServiceAuthError err(result ?
                              GoogleServiceAuthError::NONE :
                              GoogleServiceAuthError::CONNECTION_FAILED);
   heap_callback->Run(err, token, base::Time());
 }
 
 // static
 bool AndroidProfileOAuth2TokenService::Register(JNIEnv* env) {
   return RegisterNativesImpl(env);
 }