The functionality to list tree objects in the order they were seen
while traversing the commits will be used in one of the next commits,
where we teach `git describe` to describe not only commits, but blobs, too.
The change in list-objects.c is rather minimal as we'll be re-using
the infrastructure put in place of the revision walking machinery. For
example one could expect that add_pending_tree is not called, but rather
commit->tree is directly passed to the tree traversal function. This
however requires a lot more code than just emptying the queue containing
trees after each commit.
Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>