Use ChromeLauncherControllerImpl::GetItem; cleanup.

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

 // Copyright 2013 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_CHROME_LAUNCHER_CONTROLLER_IMPL_H_
 #define CHROME_BROWSER_UI_ASH_LAUNCHER_CHROME_LAUNCHER_CONTROLLER_IMPL_H_
 
 #include <list>
 #include <memory>
 
@@ skipping 45 matching lines @@
       private app_list::AppListSyncableService::Observer {
  public:
   ChromeLauncherControllerImpl(Profile* profile, ash::ShelfModel* model);
   ~ChromeLauncherControllerImpl() override;
 
   // ChromeLauncherController:
   void Init() override;
   ash::ShelfID CreateAppLauncherItem(LauncherItemController* controller,
                                      const std::string& app_id,
                                      ash::ShelfItemStatus status) override;
-  const ash::ShelfItem& GetItem(ash::ShelfID id) const override;
+  const ash::ShelfItem* GetItem(ash::ShelfID id) const override;
   void SetItemType(ash::ShelfID id, ash::ShelfItemType type) override;
   void SetItemStatus(ash::ShelfID id, ash::ShelfItemStatus status) override;
   void SetItemController(ash::ShelfID id,
                          LauncherItemController* controller) override;
   void CloseLauncherItem(ash::ShelfID id) override;
   void Pin(ash::ShelfID id) override;
   void Unpin(ash::ShelfID id) override;
   bool IsPinned(ash::ShelfID id) override;
   void TogglePinned(ash::ShelfID id) override;
   bool IsPinnable(ash::ShelfID id) const override;
@@ skipping 231 matching lines @@
   typedef std::vector<std::string> RunningAppListIds;
   typedef std::map<std::string, RunningAppListIds> RunningAppListIdMap;
   RunningAppListIdMap last_used_running_application_order_;
 
   base::WeakPtrFactory<ChromeLauncherControllerImpl> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(ChromeLauncherControllerImpl);
 };
 
 #endif  // CHROME_BROWSER_UI_ASH_LAUNCHER_CHROME_LAUNCHER_CONTROLLER_IMPL_H_