mash: Support ShelfModel access in Chrome.

ash/public/cpp/shelf_item_delegate.cc

 // Copyright 2017 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 "ash/public/cpp/shelf_item_delegate.h"
 
 namespace ash {
 
 ShelfItemDelegate::ShelfItemDelegate(const ash::ShelfID& shelf_id)
-    : shelf_id_(shelf_id), image_set_by_controller_(false) {}
+    : shelf_id_(shelf_id), binding_(this), image_set_by_controller_(false) {}
 
 ShelfItemDelegate::~ShelfItemDelegate() {}
 
+mojom::ShelfItemDelegatePtr ShelfItemDelegate::CreateInterfacePtrAndBind() {
+  return binding_.CreateInterfacePtrAndBind();
+}
+
 MenuItemList ShelfItemDelegate::GetAppMenuItems(int event_flags) {
   return MenuItemList();
 }
 
 AppWindowLauncherItemController*
 ShelfItemDelegate::AsAppWindowLauncherItemController() {
   return nullptr;
 }
 
 }  // namespace ash