Adds details about {@link StreamVariable} to the UIDL stream. Eg. in web
     * terminals Receivers are typically rendered for the client side as URLs,
     * where the client side implementation can do an http post request.
Adds details about {@link StreamVariable} to the UIDL stream. Eg. in web
     * terminals Receivers are typically rendered for the client side as URLs,
     * where the client side implementation can do an http post request. | PaintTarget.java