File API

2017-11-01: Ask Léonie for input. Might be innocuous, or might do stuff. Also, ACTION-2156 Joanie to review.
2017-11-29: Léonie will poke around about it.
2018-06-06: Deferring review.
2018-11-14: Deferring again. Check again after March 2019.
2019-06-05: Noted republishing, can't tell yet if it's ready to review. Defer to August 2019.
2019-09-11: Concluding that there are no issues for API, but may need a11y impact statement for implementation. ACTION-2212 Janina to draft.
2021-03-31: Reassigning to David Fazio.
2021-09-08: Abandoning review.