[SyncFS] Use nullptr for scoped_ptr initialization

chrome/browser/sync_file_system/sync_file_system_service.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 "chrome/browser/sync_file_system/sync_file_system_service.h"
 
 #include <string>
 
 #include "base/bind.h"
 #include "base/format_macros.h"
@@ skipping 128 matching lines @@
 //---------------------------------------------------------------------------
 // SyncProcessRunner's.
 
 // SyncProcessRunner implementation for LocalSync.
 class LocalSyncRunner : public SyncProcessRunner,
                         public LocalFileSyncService::Observer {
  public:
   LocalSyncRunner(const std::string& name,
                   SyncFileSystemService* sync_service)
       : SyncProcessRunner(name, sync_service,
-                          scoped_ptr<SyncProcessRunner::TimerHelper>(), 1),
+                          nullptr,  /* timer_helper */
+                          1  /* max_parallel_task */),
         factory_(this) {}
 
   virtual void StartSync(const SyncStatusCallback& callback) OVERRIDE {
     GetSyncService()->local_service_->ProcessLocalChange(
         base::Bind(&LocalSyncRunner::DidProcessLocalChange,
                    factory_.GetWeakPtr(), callback));
   }
 
   // LocalFileSyncService::Observer overrides.
   virtual void OnLocalChangeAvailable(int64 pending_changes) OVERRIDE {
@@ skipping 22 matching lines @@
 };
 
 // SyncProcessRunner implementation for RemoteSync.
 class RemoteSyncRunner : public SyncProcessRunner,
                          public RemoteFileSyncService::Observer {
  public:
   RemoteSyncRunner(const std::string& name,
                    SyncFileSystemService* sync_service,
                    RemoteFileSyncService* remote_service)
       : SyncProcessRunner(name, sync_service,
-                          scoped_ptr<SyncProcessRunner::TimerHelper>(), 1),
+                          nullptr,  /* timer_helper */
+                          1  /* max_parallel_task */),
         remote_service_(remote_service),
         last_state_(REMOTE_SERVICE_OK),
         factory_(this) {}
 
   virtual void StartSync(const SyncStatusCallback& callback) OVERRIDE {
     remote_service_->ProcessRemoteChange(
         base::Bind(&RemoteSyncRunner::DidProcessRemoteChange,
                    factory_.GetWeakPtr(), callback));
   }
 
@@ skipping 542 matching lines @@
        iter != remote_sync_runners_.end(); ++iter)
     ((*iter)->*method)();
 }
 
 RemoteFileSyncService* SyncFileSystemService::GetRemoteService(
     const GURL& origin) {
   return remote_service_.get();
 }
 
 }  // namespace sync_file_system