[omnibox chrome:omnibox] Keep input at top when scrolling

This only applies to screens with height greater than 900px (Pixel 2XL
has a height of 823px) in order to preserve vertical space.

Bug: 891303
Change-Id: I602f9fe75fbe45d812bf6db817e5b33f9deac6ec
Reviewed-on: https://chromium-review.googlesource.com/c/1403175
Commit-Queue: manuk hovanesian <manukh@chromium.org>
Reviewed-by: Tommy Li <tommycli@chromium.org>
Cr-Commit-Position: refs/heads/master@{#621423}
2 files changed