[cros,de-hack] Get rid of singleton for the WebUILoginScreen.

chrome/browser/chromeos/login/base_login_display_host.h

Index: chrome/browser/chromeos/login/base_login_display_host.h
diff --git a/chrome/browser/chromeos/login/base_login_display_host.h b/chrome/browser/chromeos/login/base_login_display_host.h
index 16c3f7ccd413373d74acba4ad466a3812dc753c3..466d172bae40216928198a5e0935f6ef31c77c13 100644
--- a/chrome/browser/chromeos/login/base_login_display_host.h
+++ b/chrome/browser/chromeos/login/base_login_display_host.h
@@ -22,7 +22,6 @@ class Widget;
 namespace chromeos {
 
 class ExistingUserController;
-class ViewsOobeDisplay;
 class WizardController;
 
 // An abstract base class that defines OOBE/login screen host.
@@ -45,8 +44,8 @@ class BaseLoginDisplayHost : public LoginDisplayHost,
       const GURL& start_url);
   virtual void StartSignInScreen();
 
-  // Implementation specific WizardController creation method.
-  virtual WizardController* CreateWizardController();
+  // Creates specific WizardController.
+  virtual WizardController* CreateWizardController() = 0;
 
   const gfx::Rect& background_bounds() const { return background_bounds_; }
 
@@ -70,11 +69,6 @@ class BaseLoginDisplayHost : public LoginDisplayHost,
   // OOBE and some screens (camera, recovery) controller.
   scoped_ptr<WizardController> wizard_controller_;
 
-  // Keeps views based OobeDisplay implementation if any.
-  // TODO(altimofeev): move it to ViewsLoginDisplayHost. Also see comment in
-  // the CreateWizardController().
-  scoped_ptr<ViewsOobeDisplay> oobe_display_;
-
   DISALLOW_COPY_AND_ASSIGN(BaseLoginDisplayHost);
 };