Use OnceCallback on Mojo interfaces in //ash

chrome/browser/ui/ash/launcher/app_shortcut_launcher_item_controller.h

 // 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.
 
 #ifndef CHROME_BROWSER_UI_ASH_LAUNCHER_APP_SHORTCUT_LAUNCHER_ITEM_CONTROLLER_H_
 #define CHROME_BROWSER_UI_ASH_LAUNCHER_APP_SHORTCUT_LAUNCHER_ITEM_CONTROLLER_H_
 
 #include <string>
 #include <vector>
 
@@ skipping 22 matching lines @@
 
   static std::unique_ptr<AppShortcutLauncherItemController> Create(
       const ash::ShelfID& shelf_id);
 
   std::vector<content::WebContents*> GetRunningApplications();
 
   // ash::ShelfItemDelegate overrides:
   void ItemSelected(std::unique_ptr<ui::Event> event,
                     int64_t display_id,
                     ash::ShelfLaunchSource source,
-                    const ItemSelectedCallback& callback) override;
+                    ItemSelectedCallback callback) override;
   ash::MenuItemList GetAppMenuItems(int event_flags) override;
   void ExecuteCommand(uint32_t command_id, int32_t event_flags) override;
   void Close() override;
 
   // Get the refocus url pattern, which can be used to identify this application
   // from a URL link.
   const GURL& refocus_url() const { return refocus_url_; }
   // Set the refocus url pattern. Used by unit tests.
   void set_refocus_url(const GURL& refocus_url) { refocus_url_ = refocus_url; }
 
@@ skipping 34 matching lines @@
   // keeping track of the last launch attempt.
   base::Time last_launch_attempt_;
 
   // The cached list of open app web contents shown in an application menu.
   std::vector<content::WebContents*> app_menu_items_;
 
   DISALLOW_COPY_AND_ASSIGN(AppShortcutLauncherItemController);
 };
 
 #endif  // CHROME_BROWSER_UI_ASH_LAUNCHER_APP_SHORTCUT_LAUNCHER_ITEM_CONTROLLER_H_