Revert of Fold UpdateModel into UpdateScreen.

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

Index: chrome/browser/ui/webui/chromeos/login/update_screen_handler.cc
diff --git a/chrome/browser/ui/webui/chromeos/login/update_screen_handler.cc b/chrome/browser/ui/webui/chromeos/login/update_screen_handler.cc
index 955022e46a417d505c80645c49033d634097b684..e3d767e209dd964b82ea3fe94d28bc7ebd17a98a 100644
--- a/chrome/browser/ui/webui/chromeos/login/update_screen_handler.cc
+++ b/chrome/browser/ui/webui/chromeos/login/update_screen_handler.cc
@@ -8,7 +8,7 @@
 
 #include "base/values.h"
 #include "chrome/browser/chromeos/login/oobe_screen.h"
-#include "chrome/browser/chromeos/login/screens/update_screen.h"
+#include "chrome/browser/chromeos/login/screens/update_model.h"
 #include "chrome/grit/chromium_strings.h"
 #include "chrome/grit/generated_resources.h"
 #include "components/login/localized_values_builder.h"
@@ -21,11 +21,13 @@
 
 namespace chromeos {
 
-UpdateScreenHandler::UpdateScreenHandler() : BaseScreenHandler(kJsScreenPath) {}
+UpdateScreenHandler::UpdateScreenHandler()
+    : BaseScreenHandler(kJsScreenPath), model_(nullptr), show_on_init_(false) {
+}
 
 UpdateScreenHandler::~UpdateScreenHandler() {
-  if (screen_)
-    screen_->OnViewDestroyed(this);
+  if (model_)
+    model_->OnViewDestroyed(this);
 }
 
 void UpdateScreenHandler::DeclareLocalizedValues(
@@ -74,13 +76,13 @@
 void UpdateScreenHandler::Hide() {
 }
 
-void UpdateScreenHandler::Bind(UpdateScreen* screen) {
-  screen_ = screen;
-  BaseScreenHandler::SetBaseScreen(screen_);
+void UpdateScreenHandler::Bind(UpdateModel& model) {
+  model_ = &model;
+  BaseScreenHandler::SetBaseScreen(model_);
 }
 
 void UpdateScreenHandler::Unbind() {
-  screen_ = nullptr;
+  model_ = nullptr;
   BaseScreenHandler::SetBaseScreen(nullptr);
 }