A few pro=py3 changes

mercurial_keyring.py

@@ -542,6 +542,8 b' class HTTPPasswordHandler(object):'
         where url is mercurial.util.url object already stripped of all those
         params.
         """
+        import pdb; pdb.set_trace()
+
         # mercurial.util.url, rather handy url parser
         parsed_url = util.url(authuri)
         parsed_url.query = ''
@@ -571,6 +573,10 b' def find_user_password(self, realm, auth'
     Passwords are saved in gnome keyring, OSX/Chain or other platform
     specific storage and keyed by the repository url
     """
+    # In sync with hg 5.0
+    assert isinstance(realm, (type(None), str))
+    assert isinstance(authuri, str)
+
     # Extend object attributes
     if not hasattr(self, '_pwd_handler'):
         self._pwd_handler = HTTPPasswordHandler()