Steps to reproduce

1. Go to https://firefox-rdm-orientation-type.glitch.me/
2. Enable RDM
3. Hit the "rotate viewport" button a few time and check the input values

Expected results

The input value is updated through a requestAnimationFrame loop and is set to the value of screen.orientation.type.
The 2 inputs should always have the same value as we simulate device rotation.

Actual results

The input in the iframe is never changed, it's always landscape-primary.
This does not rely on Fission at all (the iframe in the demo page is on the same origin, setting a different origin results in the same broken behaviour).

(checked 79 and the problem was already there, I guess it always was)

not sure what the initial needinfo was about (I probably should have looked at it sooner!)
This is the function that would need to be fixed: https://searchfox.org/mozilla-central/rev/fdcee847713a33b5e2b4175bb3c72d4aa2215515/docshell/base/BrowsingContext.h#590-597