Allow apps with CREATE_USERS permission to create demo users.

    <!-- @hide Allows an application to create, remove users and get the list of

         users on the device. Applications holding this permission can only create restricted,

         guest, managed, and ephemeral users. For creating other kind of users,

         guest, managed, demo, and ephemeral users. For creating other kind of users,

         {@link android.Manifest.permission#MANAGE_USERS} is needed.

         This permission is not available to third party applications. -->

    <permission android:name="android.permission.CREATE_USERS"

            UserInfo.FLAG_MANAGED_PROFILE

            | UserInfo.FLAG_EPHEMERAL

            | UserInfo.FLAG_RESTRICTED

            | UserInfo.FLAG_GUEST;

            | UserInfo.FLAG_GUEST

            | UserInfo.FLAG_DEMO;

    private static final int MIN_USER_ID = 10;

    // We need to keep process uid within Integer.MAX_VALUE.