This patch fixes a case in which computeQuadArea calculates the area size correctly, but returns the area as a negative number.
This occurs when DOM.getContentQuads returns quads in a specific order.
E.g. the array: [ { x: 463, y: 68.5 },{ x: 437, y: 68.5 },{ x: 437, y: 94.5 },{ x: 463, y: 94.5 } ] will receive area size of -676.