SVG 1.1 dynamic update tests

Tests dynamic updates of the 'width' property of the SVGMaskElement object

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

PASS maskElement.width.baseVal.valueAsString is "10%"
PASS maskElement.width.baseVal.valueAsString is "100%"
PASS successfullyParsed is true

TEST COMPLETE