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

chrome/browser/download/download_history.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.
 
 // DownloadHistory manages persisting DownloadItems to the history service by
 // observing a single DownloadManager and all its DownloadItems using an
 // AllDownloadItemNotifier.
 //
 // DownloadHistory decides whether and when to add items to, remove items from,
 // and update items in the database. DownloadHistory uses DownloadHistoryData to
@@ skipping 37 matching lines @@
 // have no control over when DownloadItems are destroyed.
 class DownloadHistoryData : public base::SupportsUserData::Data {
  public:
   static DownloadHistoryData* Get(content::DownloadItem* item) {
     base::SupportsUserData::Data* data = item->GetUserData(kKey);
     return (data == NULL) ? NULL :
       static_cast<DownloadHistoryData*>(data);
   }
 
   DownloadHistoryData(content::DownloadItem* item, int64 handle)
-    : is_adding_(false),
-      db_handle_(handle),
-      info_(NULL) {
+      : is_adding_(false), db_handle_(handle) {
     item->SetUserData(kKey, this);
   }
 
   virtual ~DownloadHistoryData() {
   }
 
   // Whether this item is currently being added to the database.
   bool is_adding() const { return is_adding_; }
   void set_is_adding(bool a) { is_adding_ = a; }
 
@@ skipping 351 matching lines @@
 
 void DownloadHistory::RemoveDownloadsBatch() {
   DCHECK(content::BrowserThread::CurrentlyOn(content::BrowserThread::UI));
   HandleSet remove_handles;
   IdSet remove_ids;
   removing_handles_.swap(remove_handles);
   removing_ids_.swap(remove_ids);
   history_->RemoveDownloads(remove_handles);
   FOR_EACH_OBSERVER(Observer, observers_, OnDownloadsRemoved(remove_ids));
 }