shill's D-Bus API methods handling the adding and removing of whitelisted IP addresses (i.e. WakeOnWiFi::AddWakeOnPacketConnection, WakeOnWiFi::RemoveWakeOnPacketConnection, WakeOnWiFi::RemoveAllWakeOnPacketConnections) will update |wake_on_packet_connections_| and return success, even if the "packet" feature is disabled. This is misleading to the remote service that called any of these methods, since shill will not actually program the NIC to wake on any of the IP addresses registered in |wake_on_packet_connections_| during suspend.

shill should instead explicitly return failure on these D-Bus calls if the packet feature is not enabled. This can be done by checking the return value of WakeOnWiFi::WakeOnWiFiPacketEnabledAndSupported(), instead of checking |wake_on_wifi_triggers_supported_| alone.