This tests indexing outside the range of the media list object.
On success, you will see a series of "PASS" messages, followed by "TEST COMPLETE".
PASS mediaList.length is 2
PASS mediaList[0] is "screen"
PASS mediaList[1] is "print"
PASS mediaList[2] is undefined.
PASS mediaList[-1] is undefined.
PASS successfullyParsed is true
TEST COMPLETE