Merge pull request #2710 from matrix-org/rav/remove_dead_code

Tiny code cleanups

synapse/app/synchrotron.py

@@ -340,11 +340,10 @@ class SyncReplicationHandler(ReplicationClientHandler):
 
         self.store = hs.get_datastore()
         self.typing_handler = hs.get_typing_handler()
+        # NB this is a SynchrotronPresence, not a normal PresenceHandler
         self.presence_handler = hs.get_presence_handler()
         self.notifier = hs.get_notifier()
 
-        self.presence_handler.sync_callback = self.send_user_sync
-
     def on_rdata(self, stream_name, token, rows):
         super(SyncReplicationHandler, self).on_rdata(stream_name, token, rows)