Chrome Version: 67.0.3396.48 (Official Build)Revision 90087faaf0402810b1c474fc36f29c3d569d5d3f-refs/branch-heads/3396@{#608} (32/64-bit) 
OS: Win(7,8,8.1,10), Linux(14.04 LTS)

What steps will reproduce the problem?
(1)Launch chrome and navigate to chrome://bookmarks/ > Organize > import bookmarks
(2)Add long history file from system such that horizontal scrollbar appears at bottom
(3)Now press 'F11' key 2-3 times and observe the scrollbar.

Actual: Flickering of scrollbar is seen after toggling browser to fullscreen mode.

Expected: No such flickering of scrollbar should be seen after toggling browser to fullscreen mode.

This is a regression issue broken in 'M66' and below is the bisect info
Good Build: 66.0.3359.33(Revision:540276)
Bad Build:  66.0.3359.45(Revision:540276)

Kindly review the attached screen-cast from the drive link (https://drive.google.com/drive/folders/1zaumJELLeE-vcLJd8KHnrk6a00_zvny3)

(Unable to narrow down the range via tool using per-revision and old script as it has same revision between this range)
CL:
https://chromium.googlesource.com/chromium/src/+log/66.0.3359.33..66.0.3359.45?pretty=fuller&n=10000

Suspecting: https://chromium.googlesource.com/chromium/src/+/cee8973f56386ace74fa77b87e81224c04ca7b26

@trchen: Could you please check whether this is caused with respect to your change, if not please help us in assigning it to the right owner.


Note:
1.Issue not seen on Mac (10.12.6,10.13.1,10.13.5) OS.
2.Issue is also seen on M-66 Stable (build #66.0.3359.181),M-68 Dev (build #68.0.3423.2) and M-68 Canary(build#68.0.3430.0)