AFAICS an "imported" gallery can only be written if you already have an
imported gallery in the first place, i.e. its something coming from an earlier
version. All the way back to 2000, so I suspect its an earlier pre-OOo feature,
which can't arise in practice with no migration from staroffice configs to
OpenOffice.org or LibreOffice.

Change-Id: I9f248baadb20633da129d3bcacce3d7f92ef7510