There were 3 packet reading functions: the "old" demux_read_packet()
that blocked (leftover from MPlayer times, but was still used until
recently by some obscure code), the "new" demux_read_packet_async(), and
the special demux_read_any_packet(), that is used by pseudo-demuxers
like demux_edl.
The first two could be used both in threaded and un-threaded mode. This
made 5 cases in total. Some bits of logic was spread across all of them.
Unify the logic. A recent commit made demux_read_packet() private, and
the code for it in threaded mode disappears. The difference between
threaded and un-threaded is minimized.
It's possible that this commit causes random regression. Enjoy.
1449bd3624