Enable strict-virtual-specifiers for iOS builds.

components/signin/ios/browser/oauth2_token_service_observer_bridge.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 COMPONENTS_SIGNIN_IOS_BROWSER_OAUTH2_TOKEN_SERVICE_OBSERVER_BRIDGE_H_
 #define COMPONENTS_SIGNIN_IOS_BROWSER_OAUTH2_TOKEN_SERVICE_OBSERVER_BRIDGE_H_
 
 #import <Foundation/Foundation.h>
 
 #include "google_apis/gaia/oauth2_token_service.h"
@@ skipping 19 matching lines @@
 
 @end
 
 // Bridge class that listens for |OAuth2TokenService| notifications and passes
 // them to its Objective-C delegate.
 class OAuth2TokenServiceObserverBridge : public OAuth2TokenService::Observer {
  public:
   OAuth2TokenServiceObserverBridge(
       OAuth2TokenService* token_service,
       id<OAuth2TokenServiceObserverBridgeDelegate> delegate);
-  virtual ~OAuth2TokenServiceObserverBridge();
+  ~OAuth2TokenServiceObserverBridge() override;
 
   // OAuth2TokenService::Observer
-  virtual void OnRefreshTokenAvailable(const std::string& account_id) override;
-  virtual void OnRefreshTokenRevoked(const std::string& account_id) override;
-  virtual void OnRefreshTokensLoaded() override;
-  virtual void OnStartBatchChanges() override;
-  virtual void OnEndBatchChanges() override;
+  void OnRefreshTokenAvailable(const std::string& account_id) override;
+  void OnRefreshTokenRevoked(const std::string& account_id) override;
+  void OnRefreshTokensLoaded() override;
+  void OnStartBatchChanges() override;
+  void OnEndBatchChanges() override;
 
  private:
   OAuth2TokenService* token_service_;  // weak
   id<OAuth2TokenServiceObserverBridgeDelegate> delegate_;
 
   DISALLOW_COPY_AND_ASSIGN(OAuth2TokenServiceObserverBridge);
 };
 
 #endif  // COMPONENTS_SIGNIN_IOS_BROWSER_OAUTH2_TOKEN_SERVICE_OBSERVER_BRIDGE_H_