Remove LauncherItemController::Launch, cleanup.

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"
 #include "chrome/browser/ui/app_list/arc/arc_app_list_prefs.h"
 #include "chrome/browser/ui/ash/launcher/arc_app_deferred_launcher_controller.h"
 #include "chrome/browser/ui/ash/launcher/arc_app_window_launcher_controller.h"
 #include "chrome/browser/ui/ash/launcher/chrome_launcher_controller.h"
 
 ArcAppDeferredLauncherItemController::ArcAppDeferredLauncherItemController(
     const std::string& arc_app_id,
     ChromeLauncherController* controller,
     int event_flags,
     const base::WeakPtr<ArcAppDeferredLauncherController>& host)
-    : LauncherItemController(arc_app_id, "", controller),
+    : LauncherItemController(arc_app_id, std::string(), controller),
       event_flags_(event_flags),
       host_(host),
       start_time_(base::Time::Now()) {}
 
 ArcAppDeferredLauncherItemController::~ArcAppDeferredLauncherItemController() {
   if (host_)
     host_->Remove(app_id());
 }
 
 base::TimeDelta ArcAppDeferredLauncherItemController::GetActiveTime() const {
   return base::Time::Now() - start_time_;
 }
 
 ash::ShelfItemDelegate::PerformedAction
 ArcAppDeferredLauncherItemController::ItemSelected(const ui::Event& event) {
   return ash::ShelfItemDelegate::kNoAction;
 }
 
 ash::ShelfAppMenuItemList ArcAppDeferredLauncherItemController::GetAppMenuItems(
     int event_flags) {
   return ash::ShelfAppMenuItemList();
 }
 
 void ArcAppDeferredLauncherItemController::Close() {
   if (host_)
     host_->Close(app_id());
 }
 
-void ArcAppDeferredLauncherItemController::Launch(ash::LaunchSource source,
-                                                  int event_flags) {}
-
 ash::ShelfItemDelegate::PerformedAction
 ArcAppDeferredLauncherItemController::Activate(ash::LaunchSource source) {
   return ash::ShelfItemDelegate::kNoAction;
 }