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

ash/system/user/tray_user.cc

 // Copyright (c) 2012 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 "ash/system/user/tray_user.h"
 
 #include "ash/ash_switches.h"
 #include "ash/root_window_controller.h"
 #include "ash/session/session_state_delegate.h"
 #include "ash/shelf/shelf_layout_manager.h"
@@ skipping 101 matching lines @@
   return user_;
 }
 
 views::View* TrayUser::CreateDetailedView(user::LoginStatus status) {
   const AccountId account_id = Shell::GetInstance()
                                    ->session_state_delegate()
                                    ->GetUserInfo(0)
                                    ->GetAccountId();
   tray::UserAccountsDelegate* delegate =
       Shell::GetInstance()->system_tray_delegate()->GetUserAccountsDelegate(
-          account_id.GetUserEmail());
+          account_id);
   if (!delegate)
     return nullptr;
   return new tray::AccountsDetailedView(this, status, delegate);
 }
 
 void TrayUser::DestroyTrayView() {
   layout_view_ = nullptr;
   avatar_ = nullptr;
   label_ = nullptr;
 }
@@ skipping 158 matching lines @@
 void TrayUser::UpdateLayoutOfItem() {
   RootWindowController* controller = GetRootWindowController(
       system_tray()->GetWidget()->GetNativeWindow()->GetRootWindow());
   if (controller && controller->shelf()) {
     UpdateAfterShelfAlignmentChange(
         controller->GetShelfLayoutManager()->GetAlignment());
   }
 }
 
 }  // namespace ash