We should use UserID object to identify users instead of username.

chrome/browser/chromeos/policy/device_local_account.cc

 // Copyright (c) 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/chromeos/policy/device_local_account.h"
 
 #include <set>
 
 #include "base/basictypes.h"
 #include "base/logging.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/string_util.h"
 #include "base/values.h"
 #include "chrome/browser/chromeos/ownership/owner_settings_service_chromeos.h"
 #include "chrome/browser/chromeos/settings/cros_settings.h"
 #include "chromeos/login/user_names.h"
 #include "chromeos/settings/cros_settings_names.h"
+#include "components/user_manager/user_id.h"
 #include "google_apis/gaia/gaia_auth_util.h"
 
 namespace policy {
 
 namespace {
 
 const char kPublicAccountDomainPrefix[] = "public-accounts";
 const char kKioskAppAccountDomainPrefix[] = "kiosk-apps";
 const char kDeviceLocalAccountDomainSuffix[] = ".device-local.localhost";
 
 }  // namespace
 
 DeviceLocalAccount::DeviceLocalAccount(Type type,
                                        const std::string& account_id,
                                        const std::string& kiosk_app_id,
                                        const std::string& kiosk_app_update_url)
     : type(type),
       account_id(account_id),
       user_id(GenerateDeviceLocalAccountUserId(account_id, type)),
       kiosk_app_id(kiosk_app_id),
       kiosk_app_update_url(kiosk_app_update_url) {
 }
 
 DeviceLocalAccount::~DeviceLocalAccount() {
 }
 
-std::string GenerateDeviceLocalAccountUserId(const std::string& account_id,
+user_manager::UserID GenerateDeviceLocalAccountUserId(const std::string& account_id,
                                              DeviceLocalAccount::Type type) {
   std::string domain_prefix;
   switch (type) {
     case DeviceLocalAccount::TYPE_PUBLIC_SESSION:
       domain_prefix = kPublicAccountDomainPrefix;
       break;
     case DeviceLocalAccount::TYPE_KIOSK_APP:
       domain_prefix = kKioskAppAccountDomainPrefix;
       break;
     case DeviceLocalAccount::TYPE_COUNT:
       NOTREACHED();
       break;
   }
-  return gaia::CanonicalizeEmail(
+
+  const std::string email = gaia::CanonicalizeEmail(
       base::HexEncode(account_id.c_str(), account_id.size()) + "@" +
       domain_prefix + kDeviceLocalAccountDomainSuffix);
+  return user_manager::UserID(std::string() /* gaia_id */, email);
 }
 
-bool IsDeviceLocalAccountUser(const std::string& user_id,
+bool IsDeviceLocalAccountUser(const user_manager::UserID& user_id,
                               DeviceLocalAccount::Type* type) {
   // For historical reasons, the guest user ID does not contain an @ symbol and
   // therefore, cannot be parsed by gaia::ExtractDomainName().
-  if (user_id == chromeos::login::kGuestUserName)
+  if (user_id == chromeos::login::GetGuestUserID())
     return false;
-  const std::string domain = gaia::ExtractDomainName(user_id);
+  const std::string domain = gaia::ExtractDomainName(user_id.GetUserEmail());
   if (!EndsWith(domain, kDeviceLocalAccountDomainSuffix, true))
     return false;
 
   const std::string domain_prefix = domain.substr(
       0, domain.size() - arraysize(kDeviceLocalAccountDomainSuffix) + 1);
 
   if (domain_prefix == kPublicAccountDomainPrefix) {
     if (type)
       *type = DeviceLocalAccount::TYPE_PUBLIC_SESSION;
     return true;
@@ skipping 99 matching lines @@
     accounts.push_back(
         DeviceLocalAccount(static_cast<DeviceLocalAccount::Type>(type),
                            account_id,
                            kiosk_app_id,
                            kiosk_app_update_url));
   }
   return accounts;
 }
 
 }  // namespace policy