Move UserContext to its own file

chrome/browser/chromeos/login/auth/login_status_consumer.cc

 // Copyright 2014 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/login/auth/login_status_consumer.h"
-#include "chrome/browser/chromeos/login/users/user.h"
 
 namespace chromeos {
 
 void LoginStatusConsumer::OnRetailModeLoginSuccess(
     const UserContext& user_context) {
   OnLoginSuccess(user_context);
 }
 
 void LoginStatusConsumer::OnPasswordChangeDetected() {
   NOTREACHED();
 }
 
 }  // namespace chromeos