Remove ShelfItemDelegate::IsDraggable; check for app list button.

chrome/browser/ui/ash/launcher/arc_app_deferred_launcher_item_controller.cc

 // Copyright 2016 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/arc_app_deferred_launcher_item_controller.h"
 
 #include <memory>
 
 #include "base/strings/utf_string_conversions.h"
 #include "chrome/browser/profiles/profile.h"
@@ skipping 42 matching lines @@
 
 bool ArcAppDeferredLauncherItemController::CanPin() const {
   return true;
 }
 
 ash::ShelfMenuModel*
 ArcAppDeferredLauncherItemController::CreateApplicationMenu(int event_flags) {
   return nullptr;
 }
 
-bool ArcAppDeferredLauncherItemController::IsDraggable() {
-  return false;
-}
-
 void ArcAppDeferredLauncherItemController::Close() {
   if (host_)
     host_->Close(app_id());
 }
 
 bool ArcAppDeferredLauncherItemController::IsVisible() const {
   return true;
 }
 
 void ArcAppDeferredLauncherItemController::Launch(ash::LaunchSource source,
                                                   int event_flags) {}
 
 ash::ShelfItemDelegate::PerformedAction
 ArcAppDeferredLauncherItemController::Activate(ash::LaunchSource source) {
   return ash::ShelfItemDelegate::kNoAction;
 }
 
 ChromeLauncherAppMenuItems
 ArcAppDeferredLauncherItemController::GetApplicationList(int event_flags) {
   return ChromeLauncherAppMenuItems();
 }