Implement MediaStreamTrackProcessor maxBufferSize support
<rdar://problem/121256478>
Submitted web-platform-tests pull request: https://github.com/web-platform-tests/wpt/pull/44095
Committed 273310@main (35a56e6b2d4a): <https://commits.webkit.org/273310@main> Reviewed commits have been landed. Closing PR #22975 and removing active labels.