This CL replaces user_manager::UserID with AccountId.

chrome/browser/chromeos/login/lock/screen_locker.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/lock/screen_locker.h"
 
 #include <string>
 #include <vector>
 
 #include "ash/ash_switches.h"
@@ skipping 232 matching lines @@
     auth_status_consumer_->OnAuthSuccess(authentication_capture_->user_context);
   }
   authentication_capture_.reset();
   weak_factory_.InvalidateWeakPtrs();
 
   VLOG(1) << "Hiding the lock screen.";
   chromeos::ScreenLocker::Hide();
 }
 
 void ScreenLocker::Authenticate(const UserContext& user_context) {
-  LOG_ASSERT(IsUserLoggedIn(user_context.GetUserID()))
+  LOG_ASSERT(IsUserLoggedIn(user_context.GetUserID().GetUserEmail()))
       << "Invalid user trying to unlock.";
 
   authentication_start_time_ = base::Time::Now();
   delegate_->SetInputEnabled(false);
   delegate_->OnAuthenticate();
 
   // Special case: supervised users. Use special authenticator.
   if (const user_manager::User* user =
-          FindUnlockUser(user_context.GetUserID())) {
+          FindUnlockUser(user_context.GetUserID().GetUserEmail())) {
     if (user->GetType() == user_manager::USER_TYPE_SUPERVISED) {
       UserContext updated_context = ChromeUserManager::Get()
                                         ->GetSupervisedUserManager()
                                         ->GetAuthentication()
                                         ->TransformKey(user_context);
       // TODO(antrim) : replace empty closure with explicit method.
       // http://crbug.com/351268
       BrowserThread::PostTask(
           BrowserThread::UI,
           FROM_HERE,
@@ skipping 232 matching lines @@
   for (user_manager::UserList::const_iterator it = users_.begin();
        it != users_.end();
        ++it) {
     if ((*it)->email() == username)
       return true;
   }
   return false;
 }
 
 }  // namespace chromeos