Tray elements behave appropriately on the multiple signin screen (more like lock screen)

chrome/browser/ui/ash/session_state_delegate_chromeos.cc

 // Copyright (c) 2013 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.
 
 #include "chrome/browser/ui/ash/session_state_delegate_chromeos.h"
 
 #include "ash/multi_profile_uma.h"
 #include "ash/session/session_state_observer.h"
 #include "base/command_line.h"
 #include "base/logging.h"
@@ skipping 196 matching lines @@
 void SessionStateDelegateChromeos::AddSessionStateObserver(
     ash::SessionStateObserver* observer) {
   session_state_observer_list_.AddObserver(observer);
 }
 
 void SessionStateDelegateChromeos::RemoveSessionStateObserver(
     ash::SessionStateObserver* observer) {
   session_state_observer_list_.RemoveObserver(observer);
 }
 
+void SessionStateDelegateChromeos::HideMultipleSigninScreen() {
+  if (this->GetSessionState() ==
+      ash::SessionStateDelegate::SESSION_STATE_LOGIN_SECONDARY) {
+    chromeos::UserAddingScreen::Get()->Cancel();
+  }
+}
+
 void SessionStateDelegateChromeos::LoggedInStateChanged() {
   SetSessionState(chromeos::LoginState::Get()->IsUserLoggedIn() ?
       SESSION_STATE_ACTIVE : SESSION_STATE_LOGIN_PRIMARY, false);
 }
 
 void SessionStateDelegateChromeos::ActiveUserChanged(
     const chromeos::User* active_user) {
   FOR_EACH_OBSERVER(ash::SessionStateObserver,
                     session_state_observer_list_,
                     ActiveUserChanged(active_user->email()));
@@ skipping 21 matching lines @@
 
   session_state_ = new_state;
   NotifySessionStateChanged();
 }
 
 void SessionStateDelegateChromeos::NotifySessionStateChanged() {
   FOR_EACH_OBSERVER(ash::SessionStateObserver,
                     session_state_observer_list_,
                     SessionStateChanged(session_state_));
 }