Move all typecasting code to individual screens.

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

 // 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.
 
 #ifndef CHROME_BROWSER_CHROMEOS_LOGIN_ENROLLMENT_ENROLLMENT_SCREEN_H_
 #define CHROME_BROWSER_CHROMEOS_LOGIN_ENROLLMENT_ENROLLMENT_SCREEN_H_
 
 #include <string>
 
 #include "base/basictypes.h"
 #include "base/compiler_specific.h"
 #include "base/gtest_prod_util.h"
 #include "base/memory/weak_ptr.h"
 #include "chrome/browser/chromeos/login/enrollment/enrollment_screen_actor.h"
 #include "chrome/browser/chromeos/login/screens/wizard_screen.h"
 #include "components/policy/core/common/cloud/cloud_policy_constants.h"
 #include "components/policy/core/common/cloud/enterprise_metrics.h"
 
 namespace chromeos {
 
+class ScreenManager;
 class ScreenObserver;
 
 // The screen implementation that links the enterprise enrollment UI into the
 // OOBE wizard.
 class EnrollmentScreen
     : public WizardScreen,
       public EnrollmentScreenActor::Controller {
  public:
   EnrollmentScreen(ScreenObserver* observer,
                    EnrollmentScreenActor* actor);
   virtual ~EnrollmentScreen();
 
+  static EnrollmentScreen* Get(ScreenManager* manager);
+
   void SetParameters(EnrollmentScreenActor::EnrollmentMode enrollment_mode,
                      const std::string& management_domain,
                      const std::string& enrollment_user,
                      const std::string& auth_token);
 
   // WizardScreen implementation:
   virtual void PrepareToShow() OVERRIDE;
   virtual void Show() OVERRIDE;
   virtual void Hide() OVERRIDE;
   virtual std::string GetName() const OVERRIDE;
@@ skipping 57 matching lines @@
   std::string auth_token_;
   int lockbox_init_duration_;
   base::WeakPtrFactory<EnrollmentScreen> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(EnrollmentScreen);
 };
 
 }  // namespace chromeos
 
 #endif  // CHROME_BROWSER_CHROMEOS_LOGIN_ENROLLMENT_ENROLLMENT_SCREEN_H_