Previously, the default history treated bottom commits the same as any
other UNINTERESTING commit, which could force it down side branches.
Consider the following history:
*A--*B---D--*F * marks !TREESAME parent paths
\ /*
`-C-'
When requesting "B..F", B is UNINTERESTING but TREESAME to D. C is
!UNINTERESTING.
So default following would go from D into the irrelevant side branch C
to A, rather than to B. Note also that if there had been an extra
!UNINTERESTING commit B1 between B and D, it wouldn't have gone down C.
Change the default following to test relevant_commit() instead of
!UNINTERESTING, so it can proceed straight from D to B, thus finishing
the traversal of that path.
Signed-off-by: Kevin Bracey <kevin@bracey.fi> Signed-off-by: Junio C Hamano <gitster@pobox.com>