I have seen something similar recently as the attachment. Issue is not seen on emulator build.

Deleted: Screenshot 2017-03-02 at 11.53.03 AM.png 79.9 KB

	Screenshot 2017-03-02 at 11.53.03 AM.png 79.9 KB View Download

btw, the above screenshot is taken on veyron_minnie 58.0.3029.0, 9286.0.0

My guess is we aren't a repaint with the correct bounds.

bisect shows the culprit CL is: https://codereview.chromium.org/2674813002.

I don't know how to fix it yet. Since original CL indicates BUG=NONE, I am going to revert it since it causes significant UI change to users.

I believe this should be RBS for M-58.

Agreed. Definitely RBS. Thanks for flagging and bisecting.

Probably best to chat with estade@ before reverting.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/bc2aafec33859883cdd69a43b301a40a79ce9327

commit bc2aafec33859883cdd69a43b301a40a79ce9327
Author: warx <warx@chromium.org>
Date: Mon Mar 06 18:30:46 2017

cros: Fix immersive fullscreen tabstrip revealing does not draw well

Changes:
When OnImmersiveRevealStarted(), if top container's layer is not marked as not filling bounds opaquely, the tabstrip may not draw correctly. It happens when user has theme installed or hovers mouse onto tabstrip.

Regression comes from: https://codereview.chromium.org/2674813002.

BUG= 697099 
TEST=device test bug does not happen

Review-Url: https://codereview.chromium.org/2728063002
Cr-Commit-Position: refs/heads/master@{#454896}

[modify] https://crrev.com/bc2aafec33859883cdd69a43b301a40a79ce9327/chrome/browser/ui/views/frame/immersive_mode_controller_ash.cc
[modify] https://crrev.com/bc2aafec33859883cdd69a43b301a40a79ce9327/ui/views/controls/label.cc

The #8 CL is pretty safe to be merged.

merge sgtm

Your change meets the bar and is auto-approved for M58. Please go ahead and merge the CL to branch 3029 manually. Please contact milestone owner if you have questions.
Owners: amineer@(clank), cmasso@(bling), bhthompson@(cros), govind@(desktop)

For more details visit https://www.chromium.org/issue-tracking/autotriage - Your friendly Sheriffbot

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/a8d551ee7fd1e0621d9b6aeaf40d60c98729e8f9

commit a8d551ee7fd1e0621d9b6aeaf40d60c98729e8f9
Author: Qiang Xu <warx@chromium.org>
Date: Tue Mar 07 19:50:45 2017

[Merge to M58] cros: Fix immersive fullscreen tabstrip revealing does not draw well

Changes:
When OnImmersiveRevealStarted(), if top container's layer is not marked as not filling bounds opaquely, the tabstrip may not draw correctly. It happens when user has theme installed or hovers mouse onto tabstrip.

Regression comes from: https://codereview.chromium.org/2674813002.

TBR=pkotwicz@chromium.org, sky@chromium.org, estade@chromium.org
BUG= 697099 
TEST=device test bug does not happen

Review-Url: https://codereview.chromium.org/2728063002
Cr-Commit-Position: refs/heads/master@{#454896}
(cherry picked from commit bc2aafec33859883cdd69a43b301a40a79ce9327)

Review-Url: https://codereview.chromium.org/2740463003 .
Cr-Commit-Position: refs/branch-heads/3029@{#49}
Cr-Branched-From: 939b32ee5ba05c396eef3fd992822fcca9a2e262-refs/heads/master@{#454471}

[modify] https://crrev.com/a8d551ee7fd1e0621d9b6aeaf40d60c98729e8f9/chrome/browser/ui/views/frame/immersive_mode_controller_ash.cc
[modify] https://crrev.com/a8d551ee7fd1e0621d9b6aeaf40d60c98729e8f9/ui/views/controls/label.cc