Revert of Fold UpdateModel into UpdateScreen.

chrome/browser/ui/webui/chromeos/login/update_screen_handler.h

Index: chrome/browser/ui/webui/chromeos/login/update_screen_handler.h
diff --git a/chrome/browser/ui/webui/chromeos/login/update_screen_handler.h b/chrome/browser/ui/webui/chromeos/login/update_screen_handler.h
index a948207333281e22c4424e93e746a84fd99265c4..c979a06850c27a4f2b7283bffecefe18ae8543ec 100644
--- a/chrome/browser/ui/webui/chromeos/login/update_screen_handler.h
+++ b/chrome/browser/ui/webui/chromeos/login/update_screen_handler.h
@@ -19,11 +19,10 @@
   UpdateScreenHandler();
   ~UpdateScreenHandler() override;
 
- private:
   // UpdateView:
   void Show() override;
   void Hide() override;
-  void Bind(UpdateScreen* screen) override;
+  void Bind(UpdateModel& model) override;
   void Unbind() override;
 
   // BaseScreenHandler:
@@ -31,10 +30,11 @@
       ::login::LocalizedValuesBuilder* builder) override;
   void Initialize() override;
 
-  UpdateScreen* screen_ = nullptr;
+ private:
+  UpdateModel* model_;
 
-  // If true, Initialize() will call Show().
-  bool show_on_init_ = false;
+  // Keeps whether screen should be shown right after initialization.
+  bool show_on_init_;
 
   DISALLOW_COPY_AND_ASSIGN(UpdateScreenHandler);
 };