cros: Remove unused WizardController::Observer.

chrome/browser/chromeos/login/wizard_controller.cc

Index: chrome/browser/chromeos/login/wizard_controller.cc
diff --git a/chrome/browser/chromeos/login/wizard_controller.cc b/chrome/browser/chromeos/login/wizard_controller.cc
index 30b5ac5004fd601dd3bdca38af0ed5bf94449ca2..630a4a5ee08b3033b454829674e041363833a138 100644
--- a/chrome/browser/chromeos/login/wizard_controller.cc
+++ b/chrome/browser/chromeos/login/wizard_controller.cc
@@ -642,19 +642,6 @@ WizardController::GetSharkConnectionListenerForTesting() {
   return shark_connection_listener_.get();
 }
 
-void WizardController::AddObserver(Observer* observer) {
-  observer_list_.AddObserver(observer);
-}
-
-void WizardController::RemoveObserver(Observer* observer) {
-  observer_list_.RemoveObserver(observer);
-}
-
-void WizardController::OnSessionStart() {
-  for (auto& observer : observer_list_)
-    observer.OnSessionStart();
-}
-
 void WizardController::SkipUpdateEnrollAfterEula() {
   skip_update_enroll_after_eula_ = true;
 }
@@ -962,9 +949,6 @@ void WizardController::ShowCurrentScreen() {
 
   smooth_show_timer_.Stop();
 
-  for (auto& observer : observer_list_)
-    observer.OnScreenChanged(current_screen_);
-
   current_screen_->Show();
 }