because I'm trying to track down a related heap corruption, and that is
much easier if the access to the array is checked by the std::vector
debug runtime
Change-Id: Ia665f5cebb7f14d88942e88b4b400ad3c28ef5d9
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/121527
Tested-by: Jenkins
Reviewed-by: Noel Grandin <noel.grandin@collabora.co.uk>