Rewrite scoped_ptr<T>(NULL) to use the default ctor.

content/browser/web_contents/web_contents_drag_win.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 "content/browser/web_contents/web_contents_drag_win.h"
 
 #include <windows.h>
 
 #include <string>
 
@@ skipping 245 matching lines @@
   // We cannot know when the target application will be done using the temporary
   // file, so schedule it to be deleted after rebooting.
   file_util::DeleteAfterReboot(download_path);
   file_util::DeleteAfterReboot(temp_dir_path);
 
   // Provide the data as file (CF_HDROP). A temporary download file with the
   // Zone.Identifier ADS (Alternate Data Stream) attached will be created.
   scoped_refptr<DragDownloadFile> download_file =
       new DragDownloadFile(
           download_path,
-          scoped_ptr<net::FileStream>(NULL),
+          scoped_ptr<net::FileStream>(),
           download_url,
           Referrer(page_url, drop_data.referrer_policy),
           page_encoding,
           web_contents_);
   ui::OSExchangeData::DownloadFileInfo file_download(base::FilePath(),
                                                      download_file.get());
   data->SetDownloadFileInfo(file_download);
 
   // Enable asynchronous operation.
   ui::OSExchangeDataProviderWin::GetIAsyncOperation(*data)->SetAsyncMode(TRUE);
@@ skipping 157 matching lines @@
       FROM_HERE,
       base::Bind(&WebContentsDragWin::CloseThread, this));
 }
 
 // static
 void WebContentsDragWin::DisableDragDropForTesting() {
   run_do_drag_drop = false;
 }
 
 }  // namespace content