Chromad: Add authentication flow

ash/public/interfaces/session_controller.mojom

 // Copyright 2016 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.
 
 module ash.mojom;
 
 import "skia/public/interfaces/bitmap.mojom";
 
 // Matches session_manager::SessionState.
 enum SessionState {
@@ skipping 41 matching lines @@
   SUPERVISED,
 
   // Kiosk app robot, logs in without authentication.
   KIOSK,
 
   // Child user, with supervised options.
   CHILD,
 
   // Android app in kiosk mode, logs in without authentication.
   ARC_KIOSK,
+
+  // Active Directory user. Authenticates against Active Directory server.
+  AD,

[dcheng, 2016/12/20 09:26:26]

Nit: Let's write this as ACTIVE_DIRECTORY, per the style guide convention of
avoiding abbreviations. Similar comment throughout the rest of this CL (AdUser
=> ActiveDirectoryUser, IsADUser => IsActiveDirectoryUser, etc)

[Roman Sorokin (ftl), 2016/12/20 12:43:59]

Done.

 };
 
 // Info about a user session in ash.
 struct UserSession {
   // A user session id for the user session. It is generated by session manager
   // (chrome) when a user session starts and never changes during the lifetime
   // of the session manager. The number starts at 1 for the first user session
   // and incremented by one for each subsequent user session.
   uint32 session_id;
 
@@ skipping 62 matching lines @@
   // Requests to lock screen.
   RequestLockScreen();
 
   // Switch to the active user with |account_id| (if the user has already signed
   // in).
   SwitchActiveUser(string account_id);
 
   // Switch the active user to the next or previous user.
   CycleActiveUser(bool next_user);
 };