CrOS: Do not allow notifications to be added during shutdown.

chrome/browser/background/background_contents_service_unittest.cc

 // Copyright (c) 2012 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/background/background_contents_service.h"
 
 #include <memory>
 #include <string>
 
 #include "base/command_line.h"
@@ skipping 175 matching lines @@
     ASSERT_TRUE(profile_manager_->SetUp());
     MessageCenterNotificationManager* manager =
         static_cast<MessageCenterNotificationManager*>(
             g_browser_process->notification_ui_manager());
     manager->SetMessageCenterTrayDelegateForTest(
         new message_center::FakeMessageCenterTrayDelegate(
             message_center::MessageCenter::Get()));
   }
 
   void TearDown() override {
-    g_browser_process->notification_ui_manager()->CancelAll();
+    g_browser_process->notification_ui_manager()->StartShutdown();
     profile_manager_.reset();
 #if !defined(OS_CHROMEOS)
     message_center::MessageCenter::Shutdown();
 #endif
     BrowserWithTestWindowTest::TearDown();
   }
 
  protected:
   // Creates crash notification for the specified extension and returns
   // the created one.
@@ skipping 200 matching lines @@
   ASSERT_TRUE(extension.get());
   CreateCrashNotification(extension);
   CreateCrashNotification(extension);
 
   message_center::MessageCenter* message_center =
       message_center::MessageCenter::Get();
   message_center::NotificationList::Notifications notifications =
       message_center->GetVisibleNotifications();
   ASSERT_EQ(1u, notifications.size());
 }