changelog: also monitor `00changelog.n` when applicable (
issue6554)
This let the locarepo's file cache detect outdated nodemap docket and reload the
changelog after `localrepo.invalidate` when applicable.
Differential Revision: https://phab.mercurial-scm.org/D11482
$ hg init
$ touch unknown
$ touch a
$ hg add a
$ hg ci -m "1"
$ touch b
$ hg add b
$ hg ci -m "2"
Should show unknown
$ hg status
? unknown
$ hg revert -r 0 --all
removing b
Should show unknown and b removed
$ hg status
R b
? unknown
Should show a and unknown
$ ls -A
.hg
a
unknown