Made a ScopedMockUserManagerEnabler to simplify UserManager mocking life-cycle.

chrome/browser/chromeos/kiosk_mode/kiosk_mode_screensaver_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/chromeos/kiosk_mode/kiosk_mode_screensaver.h"
 
 #include "base/bind.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/message_loop.h"
 #include "base/synchronization/waitable_event.h"
@@ skipping 27 matching lines @@
 
 class KioskModeScreensaverTest : public testing::Test {
  public:
   KioskModeScreensaverTest()
       : ui_thread_(BrowserThread::UI, &message_loop_),
         screensaver_(NULL),
         observer_(NULL) {
   }
 
   virtual void SetUp() OVERRIDE {
-    mock_user_manager_.reset(new MockUserManager());
-    old_user_manager_ = UserManager::Set(mock_user_manager_.get());
-    EXPECT_CALL(*mock_user_manager_, IsUserLoggedIn())
+    EXPECT_CALL(*mock_user_manager_.user_manager(), IsUserLoggedIn())
         .Times(AnyNumber())
         .WillRepeatedly(Return(false));
 
     MockDBusThreadManager* mock_dbus_thread_manager =
         new MockDBusThreadManager;
     DBusThreadManager::InitializeForTesting(mock_dbus_thread_manager);
 
     MockPowerManagerClient* power_manager =
         mock_dbus_thread_manager->mock_power_manager_client();
     EXPECT_CALL(*power_manager, HasObserver(_))
         .Times(AnyNumber())
         .WillRepeatedly(HasObserver(&observer_));
     EXPECT_CALL(*power_manager, AddObserver(_))
         .WillOnce(SaveArg<0>(&observer_));
     EXPECT_CALL(*power_manager, RemoveObserver(_))
         .WillOnce(RemoveObserver(&observer_));
     EXPECT_CALL(*power_manager, RequestIdleNotification(_))
         .Times(AnyNumber());
 
     screensaver_ = new KioskModeScreensaver();
   }
 
   virtual void TearDown() OVERRIDE {
     delete screensaver_;
-    UserManager::Set(old_user_manager_);
     DBusThreadManager::Shutdown();
   }
 
   bool LoginUserObserverRegistered() {
     return screensaver_->registrar_.IsRegistered(
         screensaver_,
         chrome::NOTIFICATION_SESSION_STARTED,
         content::NotificationService::AllSources());
   }
 
   bool PowerManagerObserverRegistered() {
     PowerManagerClient* power_manager =
         DBusThreadManager::Get()->GetPowerManagerClient();
     return power_manager->HasObserver(screensaver_);
   }
 
   MessageLoopForUI message_loop_;
   content::TestBrowserThread ui_thread_;
 
-  scoped_ptr<MockUserManager> mock_user_manager_;
-  UserManager* old_user_manager_;
+  ScopedMockUserManagerEnabler mock_user_manager_;
 
   KioskModeScreensaver* screensaver_;
   content::NotificationRegistrar registrar_;
 
   PowerManagerClient::Observer* observer_;
 };
 
 TEST_F(KioskModeScreensaverTest, CheckObservers) {
   EXPECT_TRUE(LoginUserObserverRegistered());
   EXPECT_TRUE(PowerManagerObserverRegistered());
 }
 
 TEST_F(KioskModeScreensaverTest, CheckObserversAfterUserLogin) {
   content::NotificationService::current()->Notify(
       chrome::NOTIFICATION_SESSION_STARTED,
       content::Source<UserManager>(UserManager::Get()),
       content::NotificationService::NoDetails());
 
   EXPECT_FALSE(PowerManagerObserverRegistered());
 }
 
 }  // namespace chromeos