FastPairScanner::ScanningSession and ScannerBroker::ScanningSession separate
the lifetime of FastPairScanner/ScannerBroker from the lifetime of scanning
sessions. This simplifies the cleanup.
PiperOrigin-RevId: 535675988
During the destruction of NearbyConnections, Core (which owns ClientProxy) is destructed before ServiceController (which owns EndpointManager), which means any pending tasks on the EndpointManager executor that use ClientProxy will be using
garbage memory. To fix this issue, EndpointManager::DiscardEndpoint will check
for an `is_shutdown` boolean set during ~EndpointManager before accessing
ClientProxy. The assumption is that any accessing of ClientProxy after the
destruction will be invalid.
PiperOrigin-RevId: 532581122