Bisected the issue to 5f4901a6981d8599a674983ac1b937f20ac954d1
PK should we revert?

 Issue 872085  has been merged into this issue.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/08b040e4dad5db0f1e52ed5c5a83c3a9d4a30699

commit 08b040e4dad5db0f1e52ed5c5a83c3a9d4a30699
Author: Tom Anderson <thomasanderson@chromium.org>
Date: Wed Aug 08 01:57:54 2018

Fix black bars above toolbar in refresh UI

Regression introduced by 5f4901a6981d8599a674983ac1b937f20ac954d1

BUG= 872045 
TBR=pkasting

Change-Id: I83c8e283b0ec876e1545d0ed0f783a9953d03303
Reviewed-on: https://chromium-review.googlesource.com/1166260
Reviewed-by: Thomas Anderson <thomasanderson@chromium.org>
Reviewed-by: Peter Kasting <pkasting@chromium.org>
Commit-Queue: Thomas Anderson <thomasanderson@chromium.org>
Cr-Commit-Position: refs/heads/master@{#581437}
[modify] https://crrev.com/08b040e4dad5db0f1e52ed5c5a83c3a9d4a30699/chrome/browser/ui/views/frame/opaque_browser_frame_view.cc

 Issue 872193  has been merged into this issue.

Requesting merge to M69; see https://bugs.chromium.org/p/chromium/issues/detail?id=871026#c28 for rationale.

How safe is this change to merge to M69 this late in release cycle?

This one is very safe, and we have to merge it if we decide to merge bug 854675, since it fixes an obvious visual regression.

Approving merge to M69 branch 3497 based on comment #6, #8 and per offline chat with pkasting@.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/1f45bd069a737ccc5081a1f2a374db99d771533f

commit 1f45bd069a737ccc5081a1f2a374db99d771533f
Author: Tom Anderson <thomasanderson@chromium.org>
Date: Wed Aug 22 19:17:06 2018

Fix black bars above toolbar in refresh UI

Regression introduced by 5f4901a6981d8599a674983ac1b937f20ac954d1

BUG= 872045 
TBR=pkasting

Change-Id: I83c8e283b0ec876e1545d0ed0f783a9953d03303
Reviewed-on: https://chromium-review.googlesource.com/1166260
Reviewed-by: Thomas Anderson <thomasanderson@chromium.org>
Reviewed-by: Peter Kasting <pkasting@chromium.org>
Commit-Queue: Thomas Anderson <thomasanderson@chromium.org>
Cr-Original-Commit-Position: refs/heads/master@{#581437}(cherry picked from commit 08b040e4dad5db0f1e52ed5c5a83c3a9d4a30699)
Reviewed-on: https://chromium-review.googlesource.com/1185681
Cr-Commit-Position: refs/branch-heads/3497@{#776}
Cr-Branched-From: 271eaf50594eb818c9295dc78d364aea18c82ea8-refs/heads/master@{#576753}
[modify] https://crrev.com/1f45bd069a737ccc5081a1f2a374db99d771533f/chrome/browser/ui/views/frame/opaque_browser_frame_view.cc