[webrtc-svc] Decoder compliance: Reference Scaling support (#52)

aboba has just created a new issue for https://github.com/w3c/webrtc-svc:

== Decoder compliance: Reference Scaling support ==
As noted in https://github.com/w3c/media-capabilities/issues/182, there are decoder implementations which do not support reference scaling.

Reference scaling support is not purely an SVC issue, but a decoder that does not support reference scaling also will not be able to support spatial scalability modes. 

So one potential approach would be for such a decoder to return the `scalabilityModes` that it does support. 

Is this sufficient? 

Please view or discuss this issue at https://github.com/w3c/webrtc-svc/issues/52 using your GitHub account


-- 
Sent via github-notify-ml as configured in https://github.com/w3c/github-notify-ml-config