Remove LauncherItemController::type; use ShelfItems::type.

chrome/browser/ui/ash/launcher/arc_app_launcher_browsertest.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 "ash/common/shelf/shelf_delegate.h"
 #include "ash/common/wm_shell.h"
 #include "ash/wm/window_util.h"
 #include "base/macros.h"
 #include "base/run_loop.h"
 #include "base/strings/stringprintf.h"
@@ skipping 218 matching lines @@
 
   void StopInstance() {
     arc_session_manager()->Shutdown();
     app_instance_observer()->OnInstanceClosed();
   }
 
   LauncherItemController* GetAppItemController(const std::string& id) {
     const ash::ShelfID shelf_id = shelf_delegate()->GetShelfIDForAppID(id);
     if (!shelf_id)
       return nullptr;
-    LauncherItemController* controller =
-        chrome_controller()->GetLauncherItemController(shelf_id);
-    if (!controller)
-      return nullptr;
-    DCHECK_EQ(LauncherItemController::TYPE_APP, controller->type());
-    return controller;
+    return chrome_controller()->GetLauncherItemController(shelf_id);
   }
 
   ArcAppListPrefs* app_prefs() { return ArcAppListPrefs::Get(profile()); }
 
   // Returns as AppHost interface in order to access to private implementation
   // of the interface.
   arc::mojom::AppHost* app_host() { return app_prefs(); }
 
   // Returns as AppInstance observer interface in order to access to private
   // implementation of the interface.
@@ skipping 246 matching lines @@
   app_host()->OnTaskDestroyed(2);
   EXPECT_EQ(controller2, GetAppItemController(shelf_id2));
   // Destroy task #2, this kills shelf group 2
   app_host()->OnTaskDestroyed(3);
   EXPECT_FALSE(GetAppItemController(shelf_id2));
 
   // Disable Arc, this removes app and as result kills shelf group 3.
   arc::ArcSessionManager::Get()->DisableArc();
   EXPECT_FALSE(GetAppItemController(shelf_id3));
 }