ash: Use session_manager::SessionState

ash/common/session/session_types.h

 // Copyright 2015 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 ASH_COMMON_SESSION_SESSION_TYPES_H_
 #define ASH_COMMON_SESSION_SESSION_TYPES_H_
 
 namespace ash {
 
 // The index of the user profile to use. The list is always LRU sorted so that
 // index 0 is the currently active user.
 using UserIndex = int;
 
+// Defines session state i.e. whether session is running or not and
+// whether user session is blocked by things like multi-profile login.
+enum class SessionState {

[James Cook, 2016/10/15 00:12:41]

Thanks for switching to enum class!

+  // When primary user login UI is shown i.e. after boot or sign out,
+  // no active user session exists yet.
+  LOGIN_PRIMARY = 0,
+
+  // When secondary user login UI is shown i.e. other users are
+  // already logged in and is currently adding another user to the session.
+  LOGIN_SECONDARY,
+
+  // Inside a user session (including lock screen),
+  // no login UI (primary or multi-profiles) is shown.
+  ACTIVE,
+};
+
 }  // namespace ash
 
 #endif  // ASH_COMMON_SESSION_SESSION_TYPES_H_