Test that descendant invalidation works with fullscreen pseudo classes.

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

PASS getComputedStyle(full).backgroundColor is red
PASS internals.updateStyleAndReturnAffectedElementCount() is 2
PASS getComputedStyle(full).backgroundColor is green
PASS getComputedStyle(ancestor).backgroundColor is red
PASS internals.updateStyleAndReturnAffectedElementCount() is 1
PASS getComputedStyle(ancestor).backgroundColor is green
PASS successfullyParsed is true

TEST COMPLETE