Move all typecasting code to individual screens.

chrome/browser/chromeos/login/enrollment/auto_enrollment_check_screen.h

 // Copyright 2014 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.
 
 #ifndef CHROME_BROWSER_CHROMEOS_LOGIN_ENROLLMENT_AUTO_ENROLLMENT_CHECK_SCREEN_H_
 #define CHROME_BROWSER_CHROMEOS_LOGIN_ENROLLMENT_AUTO_ENROLLMENT_CHECK_SCREEN_H_
 
 #include "base/compiler_specific.h"
 #include "base/macros.h"
 #include "base/memory/scoped_ptr.h"
 #include "chrome/browser/chromeos/login/enrollment/auto_enrollment_check_screen_actor.h"
 #include "chrome/browser/chromeos/login/enrollment/auto_enrollment_controller.h"
 #include "chrome/browser/chromeos/login/screens/error_screen.h"
 #include "chromeos/network/portal_detector/network_portal_detector.h"
 
 namespace chromeos {
 
+class ScreenManager;
 class ScreenObserver;
 
 // Handles the control flow after OOBE auto-update completes to wait for the
 // enterprise auto-enrollment check that happens as part of OOBE. This includes
 // keeping track of current auto-enrollment state and displaying and updating
 // the error screen upon failures. Similar to a screen controller, but it
 // doesn't actually drive a dedicated screen.
 class AutoEnrollmentCheckScreen
     : public AutoEnrollmentCheckScreenActor::Delegate,
       public WizardScreen,
       public NetworkPortalDetector::Observer {
  public:
   AutoEnrollmentCheckScreen(
       ScreenObserver* observer,
       AutoEnrollmentCheckScreenActor* actor);
   virtual ~AutoEnrollmentCheckScreen();
 
+  static AutoEnrollmentCheckScreen* Get(ScreenManager* manager);
+
   // Hands over OOBE control to this AutoEnrollmentCheckStep. It'll return the
   // flow back to the caller via the |screen_observer_|'s OnExit function.
   void Start();
 
   void set_auto_enrollment_controller(
       AutoEnrollmentController* auto_enrollment_controller) {
     auto_enrollment_controller_ = auto_enrollment_controller;
   }
 
   // WizardScreen implementation:
@@ skipping 49 matching lines @@
 
   NetworkPortalDetector::CaptivePortalStatus captive_portal_status_;
   policy::AutoEnrollmentState auto_enrollment_state_;
 
   DISALLOW_COPY_AND_ASSIGN(AutoEnrollmentCheckScreen);
 };
 
 }  // namespace chromeos
 
 #endif  // CHROME_BROWSER_CHROMEOS_LOGIN_ENROLLMENT_AUTO_ENROLLMENT_CHECK_SCREEN_H_