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

cloud_print/gcp20/prototype/cloud_print_requester.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 CLOUD_PRINT_GCP20_PROTOTYPE_CLOUD_REQUESTER_H_
 #define CLOUD_PRINT_GCP20_PROTOTYPE_CLOUD_REQUESTER_H_
 
 #include <string>
 #include <vector>
 
@@ skipping 116 matching lines @@
   void RequestLocalSettings(const std::string& device_id);
 
   // Updates local settings on server.
   void SendLocalSettings(const std::string& device_id,
                          const LocalSettings& settings);
 
  private:
   typedef base::Callback<void(const std::string&)> ParserCallback;
 
   // CloudPrintRequester::Delegate methods:
-  virtual void OnFetchComplete(const std::string& response) override;
-  virtual void OnFetchError(const std::string& server_api,
-                            int server_code,
-                            int server_http_code) override;
-  virtual void OnFetchTimeoutReached() override;
+  void OnFetchComplete(const std::string& response) override;
+  void OnFetchError(const std::string& server_api,
+                    int server_code,
+                    int server_http_code) override;
+  void OnFetchTimeoutReached() override;
 
   // gaia::GaiaOAuthClient::Delegate methods:
-  virtual void OnGetTokensResponse(const std::string& refresh_token,
-                                   const std::string& access_token,
-                                   int expires_in_seconds) override;
-  virtual void OnRefreshTokenResponse(const std::string& access_token,
-                                      int expires_in_seconds) override;
-  virtual void OnOAuthError() override;
-  virtual void OnNetworkError(int response_code) override;
+  void OnGetTokensResponse(const std::string& refresh_token,
+                           const std::string& access_token,
+                           int expires_in_seconds) override;
+  void OnRefreshTokenResponse(const std::string& access_token,
+                              int expires_in_seconds) override;
+  void OnOAuthError() override;
+  void OnNetworkError(int response_code) override;
 
   // Creates GET request.
   scoped_ptr<CloudPrintRequest> CreateGet(const GURL& url,
                                           const ParserCallback& callback);
 
   // Creates POST request.
   scoped_ptr<CloudPrintRequest> CreatePost(const GURL& url,
                                            const std::string& content,
                                            const std::string& mimetype,
                                            const ParserCallback& callback);
@@ skipping 51 matching lines @@
 
   ParserCallback parser_callback_;
 
   Delegate* delegate_;
 
   DISALLOW_COPY_AND_ASSIGN(CloudPrintRequester);
 };
 
 #endif  // CLOUD_PRINT_GCP20_PROTOTYPE_CLOUD_REQUESTER_H_