Broadcast Behaviour in Firefox

[DamonOehlman]

Consider the following call setup, between peers A and B:

• A has a video stream and adds it to the peer connection
• B has no video stream

In the case that B is assigned the "master" role from an rtc-signaller perspective, then it will be responsible for creating the initial offer. At the point that A receives this offer, because B has streams in the SDP it will not provide any of its streams in the answer. This is a limitation in the current firefox implementation and as such not supported at this current stage in the rtc.io modules.

A potential fix to this (if Firefox do not support this behaviour soon) is that we can ensure that the peer with the video stream (A) in this case is assigned the master role.