Artem Titov f0a34f2a30 Revert "remove mslabel and mslabel ssrc-specific attributes"
This reverts commit e3f257c4ee2079dee14ec8425eec691db3a9757c.

Reason for revert: Breaks downstream projects

Original change's description:
> remove mslabel and mslabel ssrc-specific attributes
> 
> Removes support for parsing and serializing
>   a=ssrc:1 mslabel:stream
>   a=ssrc:1 label:track
> which have been superceeded by
>   a=ssrc:1 msid:stream track
> a long time ago.
> 
> Bug: webrtc:7110
> Change-Id: I3aca47728098b6e7e049b82ed34c59426d411c41
> Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/168244
> Commit-Queue: Harald Alvestrand <hta@webrtc.org>
> Reviewed-by: Harald Alvestrand <hta@webrtc.org>
> Reviewed-by: Kári Helgason <kthelgason@webrtc.org>
> Cr-Commit-Position: refs/heads/master@{#30801}

TBR=kthelgason@webrtc.org,hta@webrtc.org,philipp.hancke@googlemail.com

Change-Id: Ibd0ad11d2dee9f54bacab3dcca61dedccfc2c120
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: webrtc:7110
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/170620
Reviewed-by: Artem Titov <titovartem@webrtc.org>
Commit-Queue: Artem Titov <titovartem@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#30805}
2020-03-16 17:52:21 +00:00
..