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

chrome/browser/signin/android_profile_oauth2_token_service.cc

Index: chrome/browser/signin/android_profile_oauth2_token_service.cc
diff --git a/chrome/browser/signin/android_profile_oauth2_token_service.cc b/chrome/browser/signin/android_profile_oauth2_token_service.cc
index abccb277a31dcb1f216406ccf66ad86fb47c474c..e62353cbf8ebc35af4a1dc9596066ad3cb1eb760 100644
--- a/chrome/browser/signin/android_profile_oauth2_token_service.cc
+++ b/chrome/browser/signin/android_profile_oauth2_token_service.cc
@@ -39,13 +39,13 @@ 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,