Test that when the scrollLayoutViewport setting is on, the scroll from window.scrollTo is applied to the layout viewport. Note that this test is pertaining to crbug.com/489206, where we want all APIs to reflect the layout viewport.

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

PASS Scroll destination reached.
PASS Scroll destination reached.
PASS successfullyParsed is true

TEST COMPLETE