Fix corner case with url pulldown

 Bug: 5534329
 The issue is that with 1px visible of the title bar the url
 pulldown code wouldn't trigger to prevent a janky animation.
 Detect whether or not the page is scrolling, and if it isn't
 then show the url bar even if it is partially visible

Change-Id: I2e7771f0e08a7dc9a6d3968e2d5e1402b1a454fa
1 file changed