The MessageReceiver and RecursiveMessageReceiver used in the test are
destroyed from the main thread, which is invalid for a thread-bound
object bound to a different thread. Fix it by destroying them with
deleteLater().
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Milan Zamazal <mzamazal@redhat.com>