Don't assume we have a GravityDirection if we turn on vertically_structured_adaptivity!
Don't assume we have a GravityDirection if we turn on vertically_structured_adaptivity!

jjo31/ATHAM-Fluidity,rjferrier/fluidity,jjo31/ATHAM-Fluidity,iakovos-panourgias/fluidity,rjferrier/fluidity,jjo31/ATHAM-Fluidity,jrper/fluidity,rjferrier/fluidity,rjferrier/fluidity,jrper/fluidity,jrper/fluidity,iakovos-panourgias/fluidity,jjo31/ATHAM-Fluidity,iakovos-panourgias/fluidity,iakovos-panourgias/fluidity,jrper/fluidity,iakovos-panourgias/fluidity,rjferrier/fluidity,jjo31/ATHAM-Fluidity,jrper/fluidity