tests/test-extra-filelog-entry.t

rust-chg: extract signal handlers from chg/procutil.c

abortmsgerrno() and debugmsg() are removed, and the public interface instead
returns success/error status. Since signal handlers can't propagate errors,
the result of kill() is just ignored.

Issue351: mq: qrefresh can create extra revlog entry

  $ echo "[extensions]" >> $HGRCPATH
  $ echo "mq=" >> $HGRCPATH

  $ hg init
  $ hg qinit

  $ echo b > b
  $ hg ci -A -m foo
  adding b

  $ echo cc > b
  $ hg qnew -f foo.diff
  $ echo b > b
  $ hg qrefresh

  $ hg debugindex b
     rev linkrev nodeid       p1           p2
       0       0 1e88685f5dde 000000000000 000000000000