The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/b01382ee0595a52205bc995129abcabae624044d

commit b01382ee0595a52205bc995129abcabae624044d
Author: Megumi Hattori <megumihattori@google.com>
Date: Wed Feb 28 01:40:29 2018

Add closing animation for inline settings.

The inline settings should have not only an opening animation but also a
closing animation in order to make it look like ARC ones. This CL adds
the closing animation.

The closing animation is also a ripple circle animation, but drawn
backwards. The inline settings have a gray background. When a gear icon
or "DONE" button is clicked, the gray background shrinks, changes into a
gray circle, gets smaller and smaller, and disappears at the point of
the gear icon.

BUG= 813698 

Change-Id: Ief41923a549e3c4cd66d9ed04ba94ee024f27086
Reviewed-on: https://chromium-review.googlesource.com/925927
Commit-Queue: Megumi Hattori <megumihattori@google.com>
Reviewed-by: Tetsui Ohkubo <tetsui@chromium.org>
Reviewed-by: Yoshiki Iguchi <yoshiki@chromium.org>
Cr-Commit-Position: refs/heads/master@{#539633}
[modify] https://crrev.com/b01382ee0595a52205bc995129abcabae624044d/ui/message_center/views/notification_view_md.cc
[modify] https://crrev.com/b01382ee0595a52205bc995129abcabae624044d/ui/message_center/views/notification_view_md_unittest.cc