The handler.
The request.
Sends the choices (gateway or restAutocompleteSender).
Clock, settings and logger.
true when an answer was sent, false after a timeout or for an expired request
(the handler is then not called).
AutocompleteTooManyChoicesError for too many choices (nothing was sent); an
error of the handler or of send as thrown.
Runs the handler until the request expires and sends its choices.