rtpssrcdemux: Fix race condition in clear-ssrc signal handler

Submitted by GstBlub

Link to original bug (#770766)

Description

Created attachment 334666
rtpssrcdemux: Fix race condition in clear-ssrc signal handler

I sometimes run into a critical error like this:

GStreamer-CRITICAL **: Padname src_1119852695 is not unique in element rtpssrcdemux2, not adding

This is because of a race condition with clear-ssrc and another rtp/rtcp packet with the same ssrc coming in, which could cause a new pad with the same name to be added before the one being cleared was actually removed.

Patch 334666, "rtpssrcdemux: Fix race condition in clear-ssrc signal handler":
0001-rtpssrcdemux-Fix-race-condition-in-clear-ssrc-signal.patch