Chrome Version:68.0.3440.15/10718.13.0 dev-channel Reks
OS:Chrome OS ARC

What steps will reproduce the problem?
(1)Sign into user >> Open Playstore >>Install any app
(2)Open its 'Download Manager' notification at ubertray while installing 
(3)Click on 'Notification settings' icon >> Click 'Done' and observe weird line trace

Actual: Weird line trace is seen while clicking 'Done' of play store Notification settings
Expected: No such weird traces should be seen

This is a Non-Regression issue seen from M-62

Note: Issue is not seen in Linux,Windows OS

Attached the screencast for your reference..

@yoshiki : Please confirm the issue.
 

Deleted: weird line trace.png 1.4 MB

	weird line trace.png 1.4 MB View Download

Deleted: Actual.mp4 5.1 MB

	Actual.mp4 5.1 MB View Download