Make OAuth2TokenService and subclasses take delegate by unique_ptr

components/signin/core/browser/profile_oauth2_token_service.cc

 // 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.
 
 #include "components/signin/core/browser/profile_oauth2_token_service.h"
 
 void ProfileOAuth2TokenService::OnRefreshTokenAvailable(
     const std::string& account_id) {
   CancelRequestsForAccount(account_id);
   ClearCacheForAccount(account_id);
 }
 
 void ProfileOAuth2TokenService::OnRefreshTokenRevoked(
     const std::string& account_id) {
   CancelRequestsForAccount(account_id);
   ClearCacheForAccount(account_id);
 }
 
 ProfileOAuth2TokenService::ProfileOAuth2TokenService(
-    OAuth2TokenServiceDelegate* delegate)
-    : OAuth2TokenService(delegate) {
+    std::unique_ptr<OAuth2TokenServiceDelegate> delegate)
+    : OAuth2TokenService(std::move(delegate)) {
   AddObserver(this);
 }
 
 ProfileOAuth2TokenService::~ProfileOAuth2TokenService() {
   RemoveObserver(this);
 }
 
 void ProfileOAuth2TokenService::Shutdown() {
   CancelAllRequests();
   GetDelegate()->Shutdown();
@@ skipping 11 matching lines @@
 }
 
 void ProfileOAuth2TokenService::RevokeCredentials(
     const std::string& account_id) {
   GetDelegate()->RevokeCredentials(account_id);
 }
 
 const net::BackoffEntry* ProfileOAuth2TokenService::GetDelegateBackoffEntry() {
   return GetDelegate()->BackoffEntry();
 }