cameraEpoch property
The host's camera epoch (host embedding API spec G-3): a fit captures it when it becomes due -- when it is scheduled, or, for the fit a view with no size yet owes, when the view is created or the request is heard (Task 2 review R-2) -- and is dropped when it has moved by the end of the frame, so a camera command made after a fit request wins. Null performs every fit, as before.
Implementation
final int Function()? cameraEpoch;