Test that the revert command updates the work tree as expected (for
submodule changes which don't result in conflicts). Add a helper function
to first revert the checked out target commit to make the last revert
produce the to-be-tested work tree.
Set the KNOWN_FAILURE_CHERRY_PICK_SEES_EMPTY_COMMIT and
KNOWN_FAILURE_NOFF_MERGE_DOESNT_CREATE_EMPTY_SUBMODULE_DIR switches to
document that revert has the similar failures.
Signed-off-by: Jens Lehmann <Jens.Lehmann@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
