[PATCH 0 of 2 STABLE] issue 2137: revlog has stale data after adding changesets

[Greg Ward]

OK, here is the fix for issue 2137.  Credit to Benoit for the actual
fix; I wrote the test.

BTW, someone already pushed my first patch (factor out _maxinline),
but only on the default branch.  It's needed on stable for the tests
here.

Greg