hbisect: pass repo into hbisect.bisect

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

--- a/mercurial/commands.py	Wed Nov 22 19:24:22 2017 -0800
+++ b/mercurial/commands.py	Thu Nov 23 14:11:27 2017 -0800
@@ -854,7 +854,7 @@
                 ui.status(_('changeset %d:%s: %s\n') % (ctx, ctx, transition))
                 hbisect.checkstate(state)
                 # bisect
-                nodes, changesets, bgood = hbisect.bisect(repo.changelog, state)
+                nodes, changesets, bgood = hbisect.bisect(repo, state)
                 # update to next check
                 node = nodes[0]
                 mayupdate(repo, node, show_stats=False)
@@ -867,7 +867,7 @@
     hbisect.checkstate(state)
 
     # actually bisect
-    nodes, changesets, good = hbisect.bisect(repo.changelog, state)
+    nodes, changesets, good = hbisect.bisect(repo, state)
     if extend:
         if not changesets:
             extendnode = hbisect.extendrange(repo, state, nodes, good)

--- a/mercurial/hbisect.py	Wed Nov 22 19:24:22 2017 -0800
+++ b/mercurial/hbisect.py	Thu Nov 23 14:11:27 2017 -0800
@@ -21,7 +21,7 @@
     error,
 )
 
-def bisect(changelog, state):
+def bisect(repo, state):
     """find the next node (if any) for testing during a bisect search.
     returns a (nodes, number, good) tuple.
 
@@ -32,6 +32,7 @@
     if searching for a first bad one.
     """
 
+    changelog = repo.changelog
     clparents = changelog.parentrevs
     skip = set([changelog.rev(n) for n in state['skip']])