This CL replaces std::string user_id in ash/* with AccountId.

chrome/browser/ui/ash/multi_user/multi_user_window_manager.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/multi_user/multi_user_window_manager.h"
 
 #include "base/logging.h"
 #include "chrome/browser/ui/ash/multi_user/multi_user_window_manager_stub.h"
 
 #if defined(OS_CHROMEOS)
@@ skipping 29 matching lines @@
   multi_user_mode_ = MULTI_PROFILE_MODE_OFF;
 #if defined(OS_CHROMEOS)
   ash::MultiProfileUMA::SessionMode mode =
       ash::MultiProfileUMA::SESSION_SINGLE_USER_MODE;
   if (!g_instance &&
       ash::Shell::GetInstance()->delegate()->IsMultiProfilesEnabled()) {
     MultiUserWindowManagerChromeOS* manager =
         new MultiUserWindowManagerChromeOS(ash::Shell::GetInstance()
                                                ->session_state_delegate()
                                                ->GetUserInfo(0)
-                                               ->GetAccountId()
-                                               .GetUserEmail());
+                                               ->GetAccountId());
     g_instance = manager;
     manager->Init();
     multi_user_mode_ = MULTI_PROFILE_MODE_SEPARATED;
     mode = ash::MultiProfileUMA::SESSION_SEPARATE_DESKTOP_MODE;
   } else if (ash::Shell::GetInstance()->delegate()->IsMultiProfilesEnabled()) {
     // The side by side mode is using the Single user window manager since all
     // windows are unmanaged side by side.
     multi_user_mode_ = MULTI_PROFILE_MODE_MIXED;
     mode = ash::MultiProfileUMA::SESSION_SIDE_BY_SIDE_MODE;
   }
@@ skipping 36 matching lines @@
 void MultiUserWindowManager::SetInstanceForTest(
     MultiUserWindowManager* instance,
     MultiProfileMode mode) {
   if (g_instance)
     DeleteInstance();
   g_instance = instance;
   multi_user_mode_ = mode;
 }
 
 }  // namespace chrome