after dependencies adopted the RtpMediaContentDescription which
this is currently aliased to.
Also move definition of AudioCodecs and VideoCodecs to the place
where codecs are defined.
BUG=webrtc:15214
Change-Id: I9b0456e1c69c8b23e0cc7665a59baae268872d9c
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/325021
Reviewed-by: Henrik Boström <hbos@webrtc.org>
Commit-Queue: Philipp Hancke <phancke@microsoft.com>
Reviewed-by: Florent Castelli <orphis@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#41020}
971f8de35a