Revision 390503

Merge r370172, r371132 from trunk:

* Insert the HTTP_IN filter uncondionally before we call
  ap_send_error_response or ap_die. This ensures that
  ap_discard_request_body called by ap_die and by ap_send_error_response works
  correctly on status codes that do not cause the connection to be dropped and
  in situations where the connection should be kept alive.

PR: 38123
Reviewed by: rpluem, niq, jerenkrantz