Scrollfps - Added scrolling for the remaining tests

Here's the code to add scrolling on the remaining 3 tests. The browser test has issues since it aborts early right now, because stop_fps() is called during the execution of the scroll. You can either reduce the scroll amount (to around 2000), change when stop_fps() is called, or add a hook to see when 'touchend' is received on the page and then do stop_fps() then. If you want to do the latter, I can help with that tomorrow.