Revert of arc: Use the new InstanceHolder for unittests

ui/arc/notification/arc_notification_manager_unittest.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 <memory>
 #include <string>
 #include <vector>
 
 #include "base/message_loop/message_loop.h"
 #include "base/run_loop.h"
@@ skipping 96 matching lines @@
   }
 
  private:
   base::MessageLoop loop_;
   std::unique_ptr<FakeArcBridgeService> service_;
   std::unique_ptr<FakeNotificationsInstance> arc_notifications_instance_;
   std::unique_ptr<ArcNotificationManager> arc_notification_manager_;
   std::unique_ptr<MockMessageCenter> message_center_;
 
   void SetUp() override {
-    arc_notifications_instance_.reset(new FakeNotificationsInstance());
+    mojom::NotificationsInstancePtr arc_notifications_instance;
+    arc_notifications_instance_.reset(
+        new FakeNotificationsInstance(GetProxy(&arc_notifications_instance)));
     service_.reset(new FakeArcBridgeService());
     message_center_.reset(new MockMessageCenter());
 
     arc_notification_manager_.reset(new ArcNotificationManager(
         service(), EmptyAccountId(), message_center_.get()));
 
     NotificationsObserver observer;
     service_->notifications()->AddObserver(&observer);
-    service_->notifications()->SetInstance(arc_notifications_instance_.get());
+    service_->OnNotificationsInstanceReady(
+        std::move(arc_notifications_instance));
 
     while (!observer.IsReady())
       loop_.RunUntilIdle();
 
     service_->notifications()->RemoveObserver(&observer);
   }
 
   void TearDown() override {
     arc_notification_manager_.reset();
     message_center_.reset();
@@ skipping 20 matching lines @@
   std::string key = CreateNotification();
   EXPECT_EQ(1u, message_center()->GetVisibleNotifications().size());
 
   {
     message_center::Notification* notification =
         *message_center()->GetVisibleNotifications().begin();
     notification->delegate()->Close(true /* by_user */);
     // |notification| gets stale here.
   }
 
+  arc_notifications_instance()->WaitForIncomingMethodCall();
+
   ASSERT_EQ(1u, arc_notifications_instance()->events().size());
   EXPECT_EQ(key, arc_notifications_instance()->events().at(0).first);
   EXPECT_EQ(mojom::ArcNotificationEvent::CLOSED,
             arc_notifications_instance()->events().at(0).second);
 }
 
 TEST_F(ArcNotificationManagerTest, NotificationRemovedByConnectionClose) {
   service()->SetReady();
   EXPECT_EQ(0u, message_center()->GetVisibleNotifications().size());
   CreateNotificationWithKey("notification1");
   CreateNotificationWithKey("notification2");
   CreateNotificationWithKey("notification3");
   EXPECT_EQ(3u, message_center()->GetVisibleNotifications().size());
 
   arc_notification_manager()->OnInstanceClosed();
 
   EXPECT_EQ(0u, message_center()->GetVisibleNotifications().size());
 }
 
 }  // namespace arc