On tvOS the profile picker shown after a background/standby resume lost
its focus highlight and the Siri Remote went dead until a force-quit.
Android TV hit the same shape with the player (#2034).
The picker and PIN dialog are pushed on the root navigator, above the
nested profile-session navigator. Nested routes still report
`isCurrent == true` under that cover, and Flutter leaves a covered
route's scope focusable, so any focus self-heal under MainScreen —
the sidebar reveal on an offline/online flip, a Libraries grid reload,
the TV browse rail — won the remote behind the picker. With menu
passthrough pinned off while the picker is up, Menu was swallowed too.
Restore the invariant once at the navigator boundary instead of at
every reclaim site: CoveredRouteFocusBoundary wraps the session in an
ExcludeFocus keyed on the root route's currency, so requests below a
cover are no-ops, and re-requests its own scope on uncover so focus
walks back to the leaf that had it (the covering route's pop culls the
excluded scope from the route scope's history before the exclusion
lifts, which is why Flutter's own restoration cannot). This makes
isRouteChainCurrent redundant; the player's guards return to plain
nested currency.
close#2239
edde746
44599549e1