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

chrome/browser/ui/ash/launcher/launcher_context_menu.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/ui/ash/launcher/launcher_context_menu.h"
 
 #include <string>
 
 #include "ash/desktop_background/user_wallpaper_delegate.h"
 #include "ash/root_window_controller.h"
@@ skipping 24 matching lines @@
 
 }  // namespace
 
 LauncherContextMenu::LauncherContextMenu(ChromeLauncherController* controller,
                                          const ash::LauncherItem* item,
                                          aura::RootWindow* root)
     : ui::SimpleMenuModel(NULL),
       controller_(controller),
       item_(*item),
       launcher_alignment_menu_(root),
-      extension_items_(NULL),
       root_window_(root) {
   DCHECK(item);
   DCHECK(root_window_);
   Init();
 }
 
 LauncherContextMenu::LauncherContextMenu(ChromeLauncherController* controller,
                                          aura::RootWindow* root)
     : ui::SimpleMenuModel(NULL),
       controller_(controller),
@@ skipping 223 matching lines @@
     case MENU_CHANGE_WALLPAPER:
       ash::Shell::GetInstance()->user_wallpaper_delegate()->
           OpenSetWallpaperPage();
       break;
 #endif
     default:
       extension_items_->ExecuteCommand(command_id, NULL,
                                        content::ContextMenuParams());
   }
 }