Add support for "Mouse Reverse Scrolling"

This is a new property applying to mice that reverses the direction of
the scroll wheel.

TEST=deploy to pyro; test new Chrome setting manually
BUG=chromium:351560

Change-Id: I51c53b793747f9d6f4012d8a3d064c45fec53ac1
Reviewed-on: https://chromium-review.googlesource.com/632977
Commit-Ready: Lann Martin <lannm@chromium.org>
Tested-by: Lann Martin <lannm@chromium.org>
Reviewed-by: Daniel Kurtz <djkurtz@chromium.org>
2 files changed