We should use UserID object to identify users instead of username.

chrome/browser/chromeos/app_mode/app_session_lifetime.cc

 // Copyright 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/chromeos/app_mode/app_session_lifetime.h"
 
 #include "base/basictypes.h"
 #include "base/bind.h"
 #include "base/lazy_instance.h"
 #include "base/message_loop/message_loop.h"
 #include "base/prefs/pref_service.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/chromeos/app_mode/kiosk_app_manager.h"
 #include "chrome/browser/chromeos/app_mode/kiosk_app_update_service.h"
 #include "chrome/browser/chromeos/app_mode/kiosk_mode_idle_app_name_notification.h"
 #include "chrome/browser/chromeos/login/demo_mode/demo_app_launcher.h"
 #include "chrome/browser/chromeos/policy/browser_policy_connector_chromeos.h"
 #include "chrome/browser/lifetime/application_lifetime.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/ui/browser.h"
 #include "chrome/browser/ui/browser_list.h"
 #include "chrome/browser/ui/browser_list_observer.h"
 #include "chrome/browser/ui/browser_window.h"
 #include "chrome/browser/ui/tabs/tab_strip_model.h"
 #include "chrome/common/pref_names.h"
 #include "chromeos/network/network_state.h"
 #include "chromeos/network/network_state_handler.h"
+#include "components/user_manager/user_id.h"
 #include "components/user_manager/user_manager.h"
 #include "content/public/browser/web_contents.h"
 #include "extensions/browser/app_window/app_window.h"
 #include "extensions/browser/app_window/app_window_registry.h"
 
 using extensions::AppWindow;
 using extensions::AppWindowRegistry;
 
 namespace chromeos {
 
@@ skipping 12 matching lines @@
     if (window_registry_)
       window_registry_->AddObserver(this);
     app_id_ = app_id;
   }
 
  private:
   // extensions::AppWindowRegistry::Observer overrides:
   void OnAppWindowRemoved(AppWindow* app_window) override {
     if (window_registry_->GetAppWindowsForApp(app_id_).empty()) {
       if (DemoAppLauncher::IsDemoAppSession(
-              user_manager::UserManager::Get()->GetActiveUser()->email())) {
+              user_manager::UserManager::Get()->GetActiveUser()->GetUserID())) {
         // If we were in demo mode, we disabled all our network technologies,
         // re-enable them.
         NetworkStateHandler* handler =
             NetworkHandler::Get()->network_state_handler();
         handler->SetTechnologyEnabled(
             NetworkTypePattern::NonVirtual(),
             true,
             chromeos::network_handler::ErrorCallback());
       }
       chrome::AttemptUserExit();
@@ skipping 53 matching lines @@
   // Binds the session lifetime with app window counts.
   CHECK(app_window_handler == NULL);
   app_window_handler.Get().Init(profile, app_id);
 
   CHECK(browser_window_handler == NULL);
   browser_window_handler.Get();
 
   // For a demo app, we don't need to either setup the update service or
   // the idle app name notification.
   if (DemoAppLauncher::IsDemoAppSession(
-          user_manager::UserManager::Get()->GetActiveUser()->email()))
+          user_manager::UserManager::Get()->GetActiveUser()->GetUserID()))
     return;
 
   // Set the app_id for the current instance of KioskAppUpdateService.
   KioskAppUpdateService* update_service =
       KioskAppUpdateServiceFactory::GetForProfile(profile);
   DCHECK(update_service);
   if (update_service)
     update_service->Init(app_id);
 
   // Start to monitor external update from usb stick.
   KioskAppManager::Get()->MonitorKioskExternalUpdate();
 
   // If the device is not enterprise managed, set prefs to reboot after update
   // and create a user security message which shows the user the application
   // name and author after some idle timeout.
   policy::BrowserPolicyConnectorChromeOS* connector =
       g_browser_process->platform_part()->browser_policy_connector_chromeos();
   if (!connector->IsEnterpriseManaged()) {
     PrefService* local_state = g_browser_process->local_state();
     local_state->SetBoolean(prefs::kRebootAfterUpdate, true);
     KioskModeIdleAppNameNotification::Initialize();
   }
 }
 
 }  // namespace chromeos