Very large replace results give huge space consumption in the
display widget, and are of dubious usefulness.

Change-Id: Ib8ad01a673ea52976befaf958f8f695aca2190ae
Reviewed-on: https://gerrit.libreoffice.org/30574Reviewed-by: Michael Meeks <michael.meeks@collabora.com>
Tested-by: Michael Meeks <michael.meeks@collabora.com>