Fixed room_name() to not fail when a timeslog has no location. Fixes a server 500 for agenda.json

 - Legacy-Id: 12118

Author: levkowetz

ietf/meeting/models.py

@@ -775,7 +775,7 @@ def __unicode__(self):
 
     @property
     def room_name(self):
-        return self.timeslot.location.name
+        return self.timeslot.location.name if self.timeslot and self.timeslot.location else None
 
     @property
     def acronym(self):