Possibly — it’s impossible to know how exactly Google is calculating the position in Google Maps. My guess is that its the fused provider, or a derivative, that leverages WiFi and other sensors along with GNSS. The only way to confirm that the device is calculating a position using L1 and L5 is the GnssStatus API, which provides a boolean flag that says which signals are being used. If the flag is set for both L1 and L5 for a satellite, then dual frequency is in use.