Chrome Version:55.0.2844.0 (Official Build) 2496c83eb444228b4c161c9ef24db2f0171d2fe5-refs/heads/master@{#415023}(32/64-bit)
OS: Windows (7,8,8.1,10),Linux (14.04 LTS),Mac OS X(10.10.5, 10.11.4)

What steps will reproduce the problem?
(1)Launch chrome and navigate to chrome://md-settings/fonts.
(2)Select drop down list under Sans serif font or Fixed width font and scroll upwards using mouse.(Kindly refer the video)
(3)Scroll upwards using mouse and observe.

Actual:Drop down list is not visible for initial fonts style option on scrolling upwards.

Expected:Drop down list should be visible properly.

This is a Regression issue broken in M-55,below is the Narrow bisect info:
https://chromium.googlesource.com/chromium/src/+log/f05e88ae004f438fcd8fb2023b51ba19a7903e48..3767fa543bcbdef5c254599a9d4d6833de4e44df?pretty=fuller&n=1000

Suspecting:r414891?

Good build:55.0.2841.0
Bad build:55.0.2842.0

Kindly help to re-assign if your change is not the cause for this issue.

 

Deleted: Actual result.mp4 757 KB

	Actual result.mp4 757 KB View Download

Deleted: Expected result.mp4 495 KB

	Expected result.mp4 495 KB View Download