Fix issue where it would be possible for the negotiated codecs to get set back to nothing. (issue #9992 reported by yehavi)

git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/1.4@69625 65c4cc65-6c06-0410-ace0-fbb531ad65f3

channels/chan_sip.c

@@ -17085,14 +17085,16 @@ static int sip_set_rtp_peer(struct ast_channel *chan, struct ast_rtp *rtp, struc
 		memset(&p->vredirip, 0, sizeof(p->vredirip));
 		changed = 1;
 	}
-	if (codecs && (p->redircodecs != codecs)) {
+	if (codecs) {
-		p->redircodecs = codecs;
+		if ((p->redircodecs != codecs)) {
-		changed = 1;
+			p->redircodecs = codecs;
-	}
+			changed = 1;
-	if ((p->capability & codecs) != p->capability) {
+		}
-		p->jointcapability &= codecs;
+		if ((p->capability & codecs) != p->capability) {
-		p->capability &= codecs;
+			p->jointcapability &= codecs;
-		changed = 1;
+			p->capability &= codecs;
+			changed = 1;
+		}
 	}
 	if (changed && !ast_test_flag(&p->flags[0], SIP_GOTREFER)) {
 		if (chan->_state != AST_STATE_UP) {	/* We are in early state */