Update {virtual,override,final} to follow C++11 style in chrome/browser/chromeos/settings.

chrome/browser/chromeos/settings/device_identity_provider.h

 // Copyright 2014 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_CHROMEOS_SETTINGS_DEVICE_IDENTITY_PROVIDER_H_
 #define CHROME_BROWSER_CHROMEOS_SETTINGS_DEVICE_IDENTITY_PROVIDER_H_
 
 #include "base/macros.h"
 #include "google_apis/gaia/identity_provider.h"
 
 namespace chromeos {
 
 class DeviceOAuth2TokenService;
 
 // Identity provider implementation backed by DeviceOAuth2TokenService.
 class DeviceIdentityProvider : public IdentityProvider {
  public:
   explicit DeviceIdentityProvider(
       chromeos::DeviceOAuth2TokenService* token_service);
-  virtual ~DeviceIdentityProvider();
+  ~DeviceIdentityProvider() override;
 
   // IdentityProvider:
-  virtual std::string GetActiveUsername() override;
-  virtual std::string GetActiveAccountId() override;
-  virtual OAuth2TokenService* GetTokenService() override;
-  virtual bool RequestLogin() override;
+  std::string GetActiveUsername() override;
+  std::string GetActiveAccountId() override;
+  OAuth2TokenService* GetTokenService() override;
+  bool RequestLogin() override;
 
  private:
   chromeos::DeviceOAuth2TokenService* token_service_;
 
   DISALLOW_COPY_AND_ASSIGN(DeviceIdentityProvider);
 };
 
 }  // namespace chromeos
 
 #endif  // CHROME_BROWSER_CHROMEOS_SETTINGS_DEVICE_IDENTITY_PROVIDER_H_