type gibberish in character map search box, click character map widget,
crash

Change-Id: Ifa3e4bce2d7e0b84cf3c5033eb819c73076daabe
Reviewed-on: https://gerrit.libreoffice.org/51775Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Miklos Vajna <vmiklos@collabora.co.uk>
(cherry picked from commit ebd78caf)