Make OAuth2TokenService and subclasses take delegate by unique_ptr

chrome/browser/chromeos/settings/device_oauth2_token_service.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 CHROME_BROWSER_CHROMEOS_SETTINGS_DEVICE_OAUTH2_TOKEN_SERVICE_H_
 #define CHROME_BROWSER_CHROMEOS_SETTINGS_DEVICE_OAUTH2_TOKEN_SERVICE_H_
 
 #include <string>
 #include <vector>
 
@@ skipping 49 matching lines @@
  private:
   friend class DeviceOAuth2TokenServiceFactory;
   friend class DeviceOAuth2TokenServiceTest;
   struct PendingRequest;
 
   // Implementation of
   // DeviceOAuth2TokenServiceDelegate::ValidationStatusDelegate.
   void OnValidationCompleted(GoogleServiceAuthError::State error) override;
 
   // Use DeviceOAuth2TokenServiceFactory to get an instance of this class.
-  // Ownership of |token_encryptor| will be taken.
-  explicit DeviceOAuth2TokenService(DeviceOAuth2TokenServiceDelegate* delegate);
+  explicit DeviceOAuth2TokenService(
+      std::unique_ptr<DeviceOAuth2TokenServiceDelegate> delegate);
   ~DeviceOAuth2TokenService() override;
 
   // Flushes |pending_requests_|, indicating the specified result.
   void FlushPendingRequests(bool token_is_valid,
                             GoogleServiceAuthError::State error);
 
   // Signals failure on the specified request, passing |error| as the reason.
   void FailRequest(RequestImpl* request, GoogleServiceAuthError::State error);
 
+  DeviceOAuth2TokenServiceDelegate* GetDeviceDelegate();
+  const DeviceOAuth2TokenServiceDelegate* GetDeviceDelegate() const;
+
   // Currently open requests that are waiting while loading the system salt or
   // validating the token.
   std::vector<PendingRequest*> pending_requests_;
 
-  DeviceOAuth2TokenServiceDelegate* delegate_;
-
   DISALLOW_COPY_AND_ASSIGN(DeviceOAuth2TokenService);
 };
 
 }  // namespace chromeos
 
 #endif  // CHROME_BROWSER_CHROMEOS_SETTINGS_DEVICE_OAUTH2_TOKEN_SERVICE_H_