This CL replaces user_manager::UserID with AccountId.

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 802 matching lines @@
 }
 
 bool SystemTrayDelegateChromeOS::IsSearchKeyMappedToCapsLock() {
   return search_key_mapped_to_ == input_method::kCapsLockKey;
 }
 
 ash::tray::UserAccountsDelegate*
 SystemTrayDelegateChromeOS::GetUserAccountsDelegate(
     const std::string& user_id) {
   if (!accounts_delegates_.contains(user_id)) {
-    const user_manager::User* user =
-        user_manager::UserManager::Get()->FindUser(user_id);
+    const user_manager::User* user = user_manager::UserManager::Get()->FindUser(
+        AccountId::FromUserEmail(user_id));
     Profile* user_profile = ProfileHelper::Get()->GetProfileByUserUnsafe(user);
     CHECK(user_profile);
     accounts_delegates_.set(
         user_id,
         scoped_ptr<ash::tray::UserAccountsDelegate>(
             new UserAccountsDelegateChromeOS(user_profile)));
   }
   return accounts_delegates_.get(user_id);
 }
 
@@ skipping 492 matching lines @@
   LOG(WARNING) << "SystemTrayDelegateChromeOS::GetChildUserMessage call while "
                << "ENABLE_SUPERVISED_USERS undefined.";
   return base::string16();
 }
 
 ash::SystemTrayDelegate* CreateSystemTrayDelegate() {
   return new SystemTrayDelegateChromeOS();
 }
 
 }  // namespace chromeos