I get the error below when trying to add a listener to a geofire query. I'm using R8 on my android project and don't know if it's the culprit.

Fatal Exception: java.lang.AssertionError: Got Datasnapshot without location with key
at com.firebase.geofire.GeoQuery.childAdded(GeoQuery.java:275)
at com.firebase.geofire.GeoQuery.access$000(GeoQuery.java:41)
at com.firebase.geofire.GeoQuery$1.onChildAdded(GeoQuery.java:62)
at com.google.firebase.database.core.ChildEventRegistration.fireEvent(ChildEventRegistration.java:79)
at com.google.firebase.database.core.view.DataEvent.fire(DataEvent.java:63)
at com.google.firebase.database.core.view.EventRaiser$1.run(EventRaiser.java:55)
at android.os.Handler.handleCallback(Handler.java:938)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:246)
at android.app.ActivityThread.main(ActivityThread.java:8625)
at java.lang.reflect.Method.invoke(Method.java)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:602)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1130)