Playback with playbin3 of MPEG TS file with two stream collections for a program does not preroll

Submitted by mki..@..il.com

Description

Created attachment 361943
MPEG TS with program, which starts with only video stream, but shortly has video and audio streams

Brief analysis done by Edward Hervey at Hackfest identified at least two problems:

mpegtsdemux does not add audio pad for second streams collection,
playbin3 unnecessary blocks streaming.

Information about TS file from tsinfo tool:
Packet 1 is PAT
Program list:
Program 1 -> PID 0100 (256)

Packet 2 is PMT with PID 0100 (256)
Program 1, version 0, PCR PID 1fff (8191)
Program streams:
PID 0101 ( 257) -> Stream type 1b ( 27) H.264/14496-10 video (MPEG-4/AVC)

Packet 159 is PMT with PID 0100 (256) - content changed
Program 1, version 1, PCR PID 0101 (257)
Program streams:
PID 0101 ( 257) -> Stream type 1b ( 27) H.264/14496-10 video (MPEG-4/AVC)
PID 0102 ( 258) -> Stream type 0f ( 15) 13818-7 Audio with ADTS transport syntax

Attachment 361943, "MPEG TS with program, which starts with only video stream, but shortly has video and audio streams":
ntv-collections-v-va.ts