Use overscroll-behavior to control swipe-navigation on CrOS

Use overscroll-behavior css property on viewport defining element to
control overscroll navigation. This patch enables this for CrOS swipe
navigation. Details can be found at
https://wicg.github.io/overscroll-behavior/

This is implemented by plumbing OverscrollBehavior to
OverscrollWindowAnimation by OnOverscrollBehaviorUpdate(). By looking
at the OverscrollBehavior value, the OverscrollWindowAnimation decides
whether to navigate or not.

Bug: 762023
Change-Id: I47e50fec12a7f508ffa04c2e53376101fc1b98be
Reviewed-on: https://chromium-review.googlesource.com/740184
Reviewed-by: Camille Lamy <clamy@chromium.org>
Reviewed-by: Sadrul Chowdhury <sadrul@chromium.org>
Reviewed-by: Majid Valipour <majidvp@chromium.org>
Commit-Queue: Sandra Sun <sunyunjia@chromium.org>
Cr-Commit-Position: refs/heads/master@{#527306}
14 files changed