changegroup: back code change of e7c618cee8df out stable

changegroup: back code change of e7c618cee8df out

The previous changeset is a simpler way of fixing issue4934 without changing the
spirit of the code. We can remove the dual call to 'delayupdate' but we keep the
tests to show that the issue is still fixed.

--- a/mercurial/changegroup.py	Fri Nov 06 12:59:09 2015 -0500
+++ b/mercurial/changegroup.py	Fri Nov 06 13:01:15 2015 -0500
@@ -406,10 +406,6 @@
                              % (changesets, revisions, files, htext))
             repo.invalidatevolatilesets()
 
-            # Call delayupdate again to ensure the transaction writepending
-            # subscriptions are still in place.
-            cl.delayupdate(tr)
-
             if changesets > 0:
                 if 'node' not in tr.hookargs:
                     tr.hookargs['node'] = hex(cl.node(clstart))