Mark Vickers

Actually, once we have #8, where `TextTrackCue.endTime` value of `Infinity` represents the end of media time, all four of my common use cases [above](https://github.com/WICG/datacue/issues/9#issue-451078568) can be solved without either resetting...

@chrisn The [resource selection algorithm](https://html.spec.whatwg.org/#concept-media-load-algorithm) destroys all text track cues when the `HTMLMediaElement` is destroyed. So, a cue cannot outlast its containing `media.duration`.

FYI: We have previously gotten MPEG confidential docs via liaison as long as they stay on the W3C Member site.