cui: More HIG fixes

Change-Id: I6e4c746de6c9393784ab831a39c3f19f0f380c07
Reviewed-on: https://gerrit.libreoffice.org/13204
Reviewed-by: Caolán McNamara <caolanm@redhat.com>
Tested-by: Caolán McNamara <caolanm@redhat.com>