Construct an S1ChordAngle that is an upper bound on the given S1Angle,
i.e. such that FastUpperBoundFrom(x).ToAngle() >= x. Unlike the S1Angle
constructor above, this method is very fast, and the bound is accurate to
within 1% for distances up to about 3100km on the Earth's surface.
Construct an S1ChordAngle that is an upper bound on the given S1Angle, i.e. such that FastUpperBoundFrom(x).ToAngle() >= x. Unlike the S1Angle constructor above, this method is very fast, and the bound is accurate to within 1% for distances up to about 3100km on the Earth's surface.