SVG 1.1 dynamic update tests

Tests dynamic updates of the 'maskContentUnits' attribute of the SVGMaskElement object

On success, you will see a series of "PASS" messages, followed by "TEST COMPLETE".

PASS maskElement.getAttribute('maskContentUnits') is "objectBoundingBox"
PASS maskElement.getAttribute('maskContentUnits') is "userSpaceOnUse"
PASS successfullyParsed is true

TEST COMPLETE