41ffaa7f2 gated picture-in-picture on FEATURE_AUTOMOTIVE and added a
settings case for it, but the assertion that case leads with — a stored
auto-PiP true surviving a read — needs supportsPictureInPicture() to be
true, and that gate ends in Platform.isAndroid || isIOS || isMacOS. The
term is false and unmockable on the Linux and Windows runners, so the
case passed on a macOS host and could never pass in CI: sanity checks
have been red for six commits on this one failure out of 4723. f13f5af6e
recorded it as a pre-existing Windows-host failure, but it entered in
this window and is red on Linux too.
Extract the gate's decision into a pure pictureInPictureAllowed that
takes the host's own capability as a parameter, the way
driver_distraction.dart already splits automotivePlaybackAllowed from its
ambient wrapper. The boolean algebra is unchanged, so the three callers
keep their behaviour; what changes is that the automotive and TV vetoes
become observable where every Platform branch is false, instead of being
vacuous on the host that gates the release.
The settings case keeps the pref-level contract on both host classes: a
stored true survives where the host supports PiP, and the gate pins it
off where it does not.
Verified with the host term forced false to emulate a Linux runner: both
files stay green, as does the full suite on macOS.
edde746
88ffe0806d