Fix cannot select and activate pinned v2app through launcher context menu

chrome/browser/ui/ash/launcher/launcher_item_controller.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_item_controller.h"
 
 #include "chrome/browser/ui/ash/launcher/chrome_launcher_controller.h"
 #include "chrome/common/extensions/extension_constants.h"
 
 LauncherItemController::LauncherItemController(
     const std::string& app_id,
     const std::string& launch_id,
     ChromeLauncherController* launcher_controller)
     : app_id_(app_id),
       launch_id_(launch_id),
       shelf_id_(0),
       launcher_controller_(launcher_controller),
       locked_(0),
       image_set_by_controller_(false) {}
 
 LauncherItemController::~LauncherItemController() {}
+
+AppWindowLauncherItemController*
+LauncherItemController::AsAppWindowLauncherItemController() {
+  return nullptr;
+}