Snav Unit Overflow And Scroll In Direction

Start End

This test ensures the correctness the following Spatial Navigation (SNav) algorithm features.

1. There is no unit overflow in the Spatial Navigation algorithm while calculating the best node candidate
   to move focus to. To test that this page positions some elements 10000000 pixels far from each other
   (distance that can considered large enough for most of the Web Pages on the Internet).

2. Make sure that a best focusable candidate only gets focused if it is visible in the current Viewport.
   Scroll-in-direction is performed otherwise.

* Navigation steps:

1. Loads this page, focus goes to "start" automatically.
2. Attempt to move focus down to "end". As it is too far and out of viewport, focus change will not happen
   and page will be scrolled a step down.
3. By sending an "End" keypress, page gets scrolled down to a place where the "end" node gets visible in the viewport.
4. Step _1_ is ran again, and "end" gets focused.