The [Constructor] extended attribute (on GeolocationSensor) is deprecated

https://w3c.github.io/geolocation-sensor/#geolocationsensor-interface

From [Travis CI](https://travis-ci.com/github/w3c/geolocation-sensor/builds/154189726):

> The `[Constructor]` extended attribute (on `GeolocationSensor`) is deprecated, please switch to a `constructor()` method.