Summary:
HTML video elements can have the `autoplay` attribute, which forces them to play automatically whenever they load on the page.
In this diff, I introduce a new prop `mediaPlaybackRequiresUserAction`, which allows us to control whether video or audio element autoplays even when `autoplay` is set.
Reviewed By: shergin
Differential Revision: D6382256
fbshipit-source-id: 617508653910d600bc43f7f68c6dfd17ab1b6dd8