applybundle: take url as argument

We allow specifying the url to carry it to hooks. This gets us closer to
'bundle1.apply(...)' and will allow us to remove regressions in multiple place
where we forget to pass the url to hooks.

mercurial/bundle2.py

@@ -302,11 +302,13 b' def _notransaction():'
     to be created"""
     raise TransactionUnavailable()
 
-def applybundle(repo, unbundler, tr, source=None, op=None):
+def applybundle(repo, unbundler, tr, source=None, url=None, op=None):
     # transform me into unbundler.apply() as soon as the freeze is lifted
     tr.hookargs['bundle2'] = '1'
     if source is not None and 'source' not in tr.hookargs:
         tr.hookargs['source'] = source
+    if url is not None and 'url' not in tr.hookargs:
+        tr.hookargs['url'] = url
     return processbundle(repo, unbundler, lambda: tr, op=op)
 
 def processbundle(repo, unbundler, transactiongetter=None, op=None):