The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/367d483bc5d1a4c7dab5fea97d203f38806cdee8

commit 367d483bc5d1a4c7dab5fea97d203f38806cdee8
Author: Kevin Schoedel <kpschoedel@chromium.org>
Date: Wed Feb 21 15:57:00 2018

Create scroller for chromecast builds.

Display-assistant UX wants scroll fling behaviour that is similar, but
probably not identical, to Android's, rather than the Blink default.
Next step(s) will either modify this to meet those requirements, or if
practical, re-merge with the Android version.

Bug: 812699
Test: duplicated Android-version test
Change-Id: Ib03f104d42b032e6b87d2dee15d2ffb6c77841a3
Reviewed-on: https://chromium-review.googlesource.com/922447
Commit-Queue: Kevin Schoedel <kpschoedel@chromium.org>
Reviewed-by: Sadrul Chowdhury <sadrul@chromium.org>
Cr-Commit-Position: refs/heads/master@{#538117}
[modify] https://crrev.com/367d483bc5d1a4c7dab5fea97d203f38806cdee8/ui/events/BUILD.gn
[add] https://crrev.com/367d483bc5d1a4c7dab5fea97d203f38806cdee8/ui/events/chromecast/scroller.cc
[add] https://crrev.com/367d483bc5d1a4c7dab5fea97d203f38806cdee8/ui/events/chromecast/scroller.h
[add] https://crrev.com/367d483bc5d1a4c7dab5fea97d203f38806cdee8/ui/events/chromecast/scroller_unittest.cc
[modify] https://crrev.com/367d483bc5d1a4c7dab5fea97d203f38806cdee8/ui/events/gestures/blink/web_gesture_curve_impl.cc