This CL replaces e-mail with AccountId on user selection screen.

chrome/browser/chromeos/login/ui/webui_login_display.h

 // 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.
 
 #ifndef CHROME_BROWSER_CHROMEOS_LOGIN_UI_WEBUI_LOGIN_DISPLAY_H_
 #define CHROME_BROWSER_CHROMEOS_LOGIN_UI_WEBUI_LOGIN_DISPLAY_H_
 
 #include <string>
 #include <vector>
 
@@ skipping 60 matching lines @@
   void ShowWrongHWIDScreen() override;
   void SetWebUIHandler(LoginDisplayWebUIHandler* webui_handler) override;
   virtual void ShowSigninScreenForCreds(const std::string& username,
                                         const std::string& password);
   bool IsShowGuest() const override;
   bool IsShowUsers() const override;
   bool IsUserSigninCompleted() const override;
   void SetDisplayEmail(const std::string& email) override;
 
   void HandleGetUsers() override;
-  void CheckUserStatus(const std::string& user_id) override;
+  void CheckUserStatus(const AccountId& account_id) override;
   bool IsUserWhitelisted(const std::string& user_id) override;
 
   // ui::UserActivityDetector implementation:
   void OnUserActivity(const ui::Event* event) override;
 
  private:
 
   // Whether to show guest login.
   bool show_guest_;
 
   // Weather to show the user pods or a GAIA sign in.
   // Public sessions are always shown.
   bool show_users_;
 
   // Whether to show add new user.
   bool show_new_user_;
 
   // Reference to the WebUI handling layer for the login screen
   LoginDisplayWebUIHandler* webui_handler_;
 
   DISALLOW_COPY_AND_ASSIGN(WebUILoginDisplay);
 };
 
 }  // namespace chromeos
 
 #endif  // CHROME_BROWSER_CHROMEOS_LOGIN_UI_WEBUI_LOGIN_DISPLAY_H_