We don't need a valve in outgoing tracks. I misunderstood the meaning of muted and enabled semantics in MediaStreamTrack.
Pull request: https://github.com/WebKit/WebKit/pull/10262
Committed 260669@main (08a6948cfbbf): <https://commits.webkit.org/260669@main> Reviewed commits have been landed. Closing PR #10262 and removing active labels.
<rdar://problem/105770988>