[Sync] Refactor ModelSafeWorker::DoWorkAndWaitUntilDone() to avoid code duplication.

components/sync/engine/ui_model_worker_unittest.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/sync/engine/ui_model_worker.h"
 
 #include <memory>
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
@@ skipping 34 matching lines @@
  public:
   SyncUIModelWorkerTest() : sync_thread_("SyncThreadForTest") {
     sync_thread_.Start();
     worker_ = new UIModelWorker(base::ThreadTaskRunnerHandle::Get());
   }
 
   void PostWorkToSyncThread(base::Closure work) {
     sync_thread_.task_runner()->PostTask(
         FROM_HERE,
         base::Bind(base::IgnoreResult(&UIModelWorker::DoWorkAndWaitUntilDone),
-                   worker_, ClosureToWorkCallback(work)));
+                   worker_, base::Passed(ClosureToWorkCallback(work))));
   }
 
  protected:
   std::unique_ptr<base::MessageLoop> ui_loop_ =
       base::MakeUnique<base::MessageLoop>();
   base::Thread sync_thread_;
   scoped_refptr<UIModelWorker> worker_;
 };
 
 }  // namespace
@@ skipping 44 matching lines @@
   // RequestStop() is called. However, it doesn't fail (no flakes).
   base::PlatformThread::Sleep(TestTimeouts::tiny_timeout());
 
   // The sync thread shouldn't wait for the WorkCallback to run on the UI thread
   // after RequestStop() is called.
   worker_->RequestStop();
   sync_thread_.Stop();
 }
 
 }  // namespace syncer