These were broken by b5373e9. The problem is that the code
marks the month and year with "-1" for "we don't know it
yet", but the month and year code paths were not adjusted to
fill in the current time before doing their calculations
(whereas other units follow a different code path and are
fine).
Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>