We want to be able to import, and then export, using the same marks, so
that we don't push things that the other side already received.
Unfortunately, fast-export doesn't store blobs in the marks, but
fast-import does. This creates a mismatch when fast export is reusing a
mark that was previously stored by fast-import.
There is no point in one tool saving blobs, and the other not, but for
now let's just check in fast-export that the objects are indeed commits.
Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>