Add ARC++ kiosk menu items and ability to start kiosk session.

chromeos/login/auth/login_performer.h

Index: chromeos/login/auth/login_performer.h
diff --git a/chromeos/login/auth/login_performer.h b/chromeos/login/auth/login_performer.h
index 3c814ea398b210ccc5da8c8d31cf1bd02e08f7ec..d9f16ef94ac309b894d20bf0a512e0729685e762 100644
--- a/chromeos/login/auth/login_performer.h
+++ b/chromeos/login/auth/login_performer.h
@@ -83,6 +83,9 @@ class CHROMEOS_EXPORT LoginPerformer : public AuthStatusConsumer {
   void LoginAsKioskAccount(const AccountId& app_account_id,
                            bool use_guest_mount);
 
+  // Performs a login into the ARC kiosk mode account with |arc_app_account_id|.
+  void LoginAsArcKioskAccount(const AccountId& arc_app_account_id);
+
   // AuthStatusConsumer implementation:
   void OnAuthFailure(const AuthFailure& error) override;
   void OnAuthSuccess(const UserContext& user_context) override;