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

chrome/browser/ui/ash/system_tray_delegate_chromeos.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/system_tray_delegate_chromeos.h"
 
 #include <algorithm>
 #include <set>
 #include <string>
 #include <vector>
@@ skipping 557 matching lines @@
           ->GetUsersAllowedForMultiProfile()
           .size()) {
     // Don't show dialog if any logged in user in multi-profiles session
     // dismissed it.
     bool show_intro = true;
     const user_manager::UserList logged_in_users =
         user_manager::UserManager::Get()->GetLoggedInUsers();
     for (user_manager::UserList::const_iterator it = logged_in_users.begin();
          it != logged_in_users.end();
          ++it) {
-      show_intro &= !multi_user_util::GetProfileFromUserID(
-                         multi_user_util::GetUserIDFromEmail((*it)->email()))
-                         ->GetPrefs()
-                         ->GetBoolean(prefs::kMultiProfileNeverShowIntro);
+      show_intro &=
+          !multi_user_util::GetProfileFromAccountId((*it)->GetAccountId())
+               ->GetPrefs()
+               ->GetBoolean(prefs::kMultiProfileNeverShowIntro);
       if (!show_intro)
         break;
     }
     if (show_intro) {
       base::Callback<void(bool)> on_accept =
           base::Bind(&OnAcceptMultiprofilesIntro);
       ShowMultiprofilesIntroDialog(on_accept);
     } else {
       UserAddingScreen::Get()->Start();
     }
@@ skipping 219 matching lines @@
   SetProfile(ProfileManager::GetActiveUserProfile());
   GetSystemTrayNotifier()->NotifyUserUpdate();
 }
 
 bool SystemTrayDelegateChromeOS::IsSearchKeyMappedToCapsLock() {
   return search_key_mapped_to_ == input_method::kCapsLockKey;
 }
 
 ash::tray::UserAccountsDelegate*
 SystemTrayDelegateChromeOS::GetUserAccountsDelegate(
-    const std::string& user_id) {
-  if (!accounts_delegates_.contains(user_id)) {
-    const user_manager::User* user = user_manager::UserManager::Get()->FindUser(
-        AccountId::FromUserEmail(user_id));
+    const AccountId& account_id) {
+  auto it = accounts_delegates_.find(account_id);
+  if (it == accounts_delegates_.end()) {
+    const user_manager::User* user =
+        user_manager::UserManager::Get()->FindUser(account_id);
     Profile* user_profile = ProfileHelper::Get()->GetProfileByUserUnsafe(user);
     CHECK(user_profile);
     accounts_delegates_.set(
-        user_id,
-        scoped_ptr<ash::tray::UserAccountsDelegate>(
-            new UserAccountsDelegateChromeOS(user_profile)));
+        account_id, scoped_ptr<ash::tray::UserAccountsDelegate>(
+                        new UserAccountsDelegateChromeOS(user_profile)));
+    it = accounts_delegates_.find(account_id);
   }
-  return accounts_delegates_.get(user_id);
+  return it->second;
 }
 
 void SystemTrayDelegateChromeOS::AddCustodianInfoTrayObserver(
     ash::CustodianInfoTrayObserver* observer) {
   custodian_info_changed_observers_.AddObserver(observer);
 }
 
 void SystemTrayDelegateChromeOS::RemoveCustodianInfoTrayObserver(
     ash::CustodianInfoTrayObserver* observer) {
   custodian_info_changed_observers_.RemoveObserver(observer);
@@ skipping 403 matching lines @@
     policy::CloudPolicyStore* store) {
   UpdateEnterpriseDomain();
 }
 
 void SystemTrayDelegateChromeOS::OnStoreError(policy::CloudPolicyStore* store) {
   UpdateEnterpriseDomain();
 }
 
 // Overridden from ash::SessionStateObserver
 void SystemTrayDelegateChromeOS::UserAddedToSession(
-    const std::string& user_id) {
+    const AccountId& /*account_id*/) {
   GetSystemTrayNotifier()->NotifyUserAddedToSession();
 }
 
 void SystemTrayDelegateChromeOS::ActiveUserChanged(
-    const std::string& /* user_id */) {
-}
+    const AccountId& /* user_id */) {}
 
 // Overridden from chrome::BrowserListObserver.
 void SystemTrayDelegateChromeOS::OnBrowserRemoved(Browser* browser) {
   NotifyIfLastWindowClosed();
 }
 
 // Overridden from extensions::AppWindowRegistry::Observer.
 void SystemTrayDelegateChromeOS::OnAppWindowRemoved(
     extensions::AppWindow* app_window) {
   NotifyIfLastWindowClosed();
@@ skipping 54 matching lines @@
   LOG(WARNING) << "SystemTrayDelegateChromeOS::GetChildUserMessage call while "
                << "ENABLE_SUPERVISED_USERS undefined.";
   return base::string16();
 }
 
 ash::SystemTrayDelegate* CreateSystemTrayDelegate() {
   return new SystemTrayDelegateChromeOS();
 }
 
 }  // namespace chromeos