hbisect: pass repo into hbisect.bisect
Pass repo into the bisect function to get more flexibility in what we can call.
This will allow us to use revsets to rewrite parts of the ancestor and children
calculation in later patches.
Test Plan:
python run-tests.py test-bisect*
Differential Revision: https://phab.mercurial-scm.org/D1497
$ 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