Fix bounding box rect always having a x: 0, y: 0 due to using CGRectZero instead of CGRectNull.
Fix bounding box rect always having a x: 0, y: 0 due to using CGRectZero instead of CGRectNull.

GenerallyHelpfulSoftware/SVGgh,GenerallyHelpfulSoftware/SVGgh,GenerallyHelpfulSoftware/SVGgh