This CL replaces user_manager::UserID with AccountId.

chrome/browser/chromeos/login/existing_user_controller.h

 // Copyright (c) 2012 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_EXISTING_USER_CONTROLLER_H_
 #define CHROME_BROWSER_CHROMEOS_LOGIN_EXISTING_USER_CONTROLLER_H_
 
 #include <string>
 
 #include "base/basictypes.h"
@@ skipping 227 matching lines @@
   // Callback invoked when |oauth2_token_initializer_| has finished.
   void OnOAuth2TokensFetched(bool success, const UserContext& user_context);
 
   // Public session auto-login timer.
   scoped_ptr<base::OneShotTimer> auto_login_timer_;
 
   // Public session auto-login timeout, in milliseconds.
   int public_session_auto_login_delay_;
 
   // Username for public session auto-login.
   std::string public_session_auto_login_username_;

[achuithb, 2015/10/28 23:11:45]

AccountId?

[Alexander Alekseev, 2015/10/29 02:00:40]

This will be cleared in another CL.

My code update algorithm should be like this:
1) Update a set of files, replacing std::string with AccountId.
2) Make temporary conversions in all adjacent files to make the code compile.
This introduces a set of GetUserEmail / FromUserEmail calls.
3) Land CL.

Then, start a new CL with "replace FromUserEmail/GetUserEmail with AccountId
objects further".

This CL is about replacing UserID in user_manager namespace. If I start
replacing strings with AccountIds further, it would grow enormously. I'll do it
in a next couple of CLs.

This member is translated to AccountId:

chrome/browser/chromeos/login/existing_user_controller.cc:850:     
AccountId::FromUserEmail(public_session_auto_login_username_));

This means that it is pending for transformation due to call to FromUserEmail.

 
   // Used to execute login operations.
   scoped_ptr<LoginPerformer> login_performer_;
 
   // Delegate to forward all authentication status events to.
   // Tests can use this to receive authentication status events.
   AuthStatusConsumer* auth_status_consumer_;
 
   // Username of the last login attempt.

[achuithb, 2015/10/28 23:11:45]

AccountId

[Alexander Alekseev, 2015/10/29 02:00:40]

Done.

-  std::string last_login_attempt_username_;
+  AccountId last_login_attempt_account_id_ = EmptyAccountId();
 
   // OOBE/login display host.
   LoginDisplayHost* host_;
 
   // Login UI implementation instance.
   scoped_ptr<LoginDisplay> login_display_;
 
   // Number of login attempts. Used to show help link when > 1 unsuccessful
   // logins for the same user.
   size_t num_login_attempts_;
@@ skipping 56 matching lines @@
 
   // Factory of callbacks.
   base::WeakPtrFactory<ExistingUserController> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(ExistingUserController);
 };
 
 }  // namespace chromeos
 
 #endif  // CHROME_BROWSER_CHROMEOS_LOGIN_EXISTING_USER_CONTROLLER_H_