queue, queue2: make segment position readable so that stalled/starved queues are obvious
Submitted by min..@..arp.fm
It is currently difficult to tell which queues are allowing data to flow and which queues are stalled, making stalled complex pipelines very difficult to debug.
Expose the queue->src_segment.position and queue->sink_segment.position containing the PTS/DTS of the last buffer into and out of the queue to clearly show which queues are lagging behind and stalling the pipeline.
This also clearly shows queues that have never delivered data, as opposed to queues that are just empty.