Adapt Chrome OS related part of ChildAccountService.

chrome/browser/ui/ash/system_tray_delegate_chromeos.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/ui/ash/system_tray_delegate_chromeos.h"
 
 #include <algorithm>
 #include <set>
 #include <string>
 #include <vector>
@@ skipping 822 matching lines @@
   custodian_info_changed_observers_.RemoveObserver(observer);
 }
 
 void SystemTrayDelegateChromeOS::UserAddedToSession(
     const user_manager::User* active_user) {
 }
 
 void SystemTrayDelegateChromeOS::UserChangedSupervisedStatus(
     user_manager::User* user) {
   Profile* user_profile = ProfileHelper::Get()->GetProfileByUser(user);
-  DCHECK(user_profile);
 
-  if (session_started_ && user_profile_ == user_profile) {
+  if (session_started_ &&
+      user_profile != NULL &&

[Marc Treib, 2014/12/10 12:42:36]

Maybe add a comment explaining when user_profile can be null?

+      user_profile_ == user_profile) {
     ash::Shell::GetInstance()->UpdateAfterLoginStatusChange(
         GetUserLoginStatus());
   }
 }
 
 ash::SystemTray* SystemTrayDelegateChromeOS::GetPrimarySystemTray() {
   return ash::Shell::GetInstance()->GetPrimarySystemTray();
 }
 
 ash::SystemTrayNotifier* SystemTrayDelegateChromeOS::GetSystemTrayNotifier() {
@@ skipping 435 matching lines @@
     accessibility_subscription_.reset();
   else
     OnAccessibilityModeChanged(details.notify);
 }
 
 ash::SystemTrayDelegate* CreateSystemTrayDelegate() {
   return new SystemTrayDelegateChromeOS();
 }
 
 }  // namespace chromeos