cros: Cleanup lock screen and OOBE C++ backing code.

chrome/browser/chromeos/shutdown_policy_browsertest.cc

 // Copyright 2015 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 "ash/common/login_status.h"
 #include "ash/common/strings/grit/ash_strings.h"
 #include "ash/common/system/date/date_default_view.h"
@@ skipping 212 matching lines @@
     // Bring up the locker screen.
     ScreenLocker::Show();
     std::unique_ptr<test::ScreenLockerTester> tester(ScreenLocker::GetTester());
     tester->EmulateWindowManagerReady();
     content::WindowedNotificationObserver lock_state_observer(
         chrome::NOTIFICATION_SCREEN_LOCK_STATE_CHANGED,
         content::NotificationService::AllSources());
     if (!tester->IsLocked())
       lock_state_observer.Wait();
     ScreenLocker* screen_locker = ScreenLocker::default_screen_locker();
-    WebUIScreenLocker* web_ui_screen_locker =
-        static_cast<WebUIScreenLocker*>(screen_locker->delegate());
+    WebUIScreenLocker* web_ui_screen_locker = screen_locker->web_ui();
     ASSERT_TRUE(web_ui_screen_locker);
     content::WebUI* web_ui = web_ui_screen_locker->GetWebUI();
     ASSERT_TRUE(web_ui);
     contents_ = web_ui->GetWebContents();
     ASSERT_TRUE(contents_);
 
     // Wait for the login UI to be ready.
     WaitUntilOobeUIIsReady(
         static_cast<OobeUI*>(web_ui->GetController()));
   }
@@ skipping 82 matching lines @@
   PrepareAndRunScript("restart-header-bar-item", false);
   PrepareAndRunScript("shutdown-header-bar-item", true);
 
   UpdateRebootOnShutdownPolicy(false);
   RefreshDevicePolicy();
   PrepareAndRunScript("restart-header-bar-item", true);
   PrepareAndRunScript("shutdown-header-bar-item", false);
 }
 
 }  // namespace chromeos