Chrome Android will relax its autoplay restrictions to allow muted videos to autoplay. The rationale is that there are other ways to render pixels on the screen. They are all worse for battery usage (h264 in js) and/or bandwidth consumption (GIF).
Changes to API surface:
No change to API surface but change in behaviour. The API is flexible enough to properly handle this new case.
Public standards discussion: https://github.com/whatwg/html/issues/976
Support in other browsers:
Internet Explorer: No public signal.
Firefox: No public signal.
Safari: Public support.