Don't sent in-dialog requests like UPDATE when Asterisk has not yet received a Contact URI from a UAS

git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/1.8@341366 65c4cc65-6c06-0410-ace0-fbb531ad65f3

channels/chan_sip.c

@@ -12547,7 +12547,7 @@ static void update_connectedline(struct sip_pvt *p, const void *data, size_t dat
 			ast_set_flag(&p->flags[0], SIP_OUTGOING);
 			p->invitestate = INV_CALLING;
 			send_request(p, &req, XMIT_CRITICAL, p->ocseq);
-		} else if (is_method_allowed(&p->allowed_methods, SIP_UPDATE)) {
+		} else if ((is_method_allowed(&p->allowed_methods, SIP_UPDATE)) && (!ast_strlen_zero(p->okcontacturi))) { 
 			reqprep(&req, p, SIP_UPDATE, 0, 1);
 			add_rpid(&req, p);
 			add_header(&req, "X-Asterisk-rpid-update", "Yes");