This is meant to be mechanical, full conversion to HtmlWriter has to be
done step by step in follow-up commits.

Change-Id: Ieab096f8c9936f0ecad029fbdfb51da7412ad83e
Reviewed-on: https://gerrit.libreoffice.org/50449Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Miklos Vajna <vmiklos@collabora.co.uk>