darwin: Fix narrowing issue in S2CellId::FromFaceIJ
darwin: Fix narrowing issue in S2CellId::FromFaceIJ

laramiel/s2-geometry-library,micolous/s2-geometry-library,Noctem/pogeo,yjwong/s2-geometry-library,micolous/s2-geometry-library,Noctem/pogeo,yjwong/s2-geometry-library,micolous/s2-geometry-library,laramiel/s2-geometry-library,Noctem/pogeo,laramiel/s2-geometry-library,yjwong/s2-geometry-library,micolous/s2-geometry-library,yjwong/s2-geometry-library,Noctem/pogeo