dagop: compute depth in revancestors() generator
Surprisingly, this makes revset benchmark slightly faster. I don't know why,
but it appears that wrapping -inputrev by tuple is the key. So I decided to
just enable depth computation by default.
# reverse(ancestors(tip)) using hg repo
1) 0.081051
2) 0.075408
$ echo "[extensions]" >> $HGRCPATH
$ echo "mq=" >> $HGRCPATH
$ hg init
$ echo 'base' > base
$ hg ci -Ambase
adding base
$ hg qnew -mmqbase mqbase
$ hg qsave
$ hg qrestore 2
restoring status: hg patches saved state