Clean up potentially leaky use of base::DeletePointer.

components/history/core/browser/history_backend.cc

 // Copyright (c) 2012 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/history/core/browser/history_backend.h"
 
 #include <algorithm>
 #include <functional>
 #include <list>
 #include <map>
@@ skipping 142 matching lines @@
     : task_(task.Pass()), origin_loop_(origin_loop), is_canceled_(is_canceled) {
   DCHECK(task_);
   DCHECK(origin_loop_.get());
   DCHECK(!is_canceled_.is_null());
 }
 
 QueuedHistoryDBTask::~QueuedHistoryDBTask() {
   // Ensure that |task_| is destroyed on its origin thread.
   origin_loop_->PostTask(FROM_HERE,
                          base::Bind(&base::DeletePointer<HistoryDBTask>,
-                                    base::Unretained(task_.release())));
+                                    base::Passed(&task_)));
 }
 
 bool QueuedHistoryDBTask::is_canceled() {
   return is_canceled_.Run();
 }
 
 bool QueuedHistoryDBTask::Run(HistoryBackend* backend, HistoryDatabase* db) {
   return task_->RunOnDBThread(backend, db);
 }
 
@@ skipping 2461 matching lines @@
   return true;
 }
 
 HistoryClient* HistoryBackend::GetHistoryClient() {
   if (history_client_)
     history_client_->BlockUntilBookmarksLoaded();
   return history_client_;
 }
 
 }  // namespace history