The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/28e7aa57ce877194747cf5b6837133252e7f49e2

commit 28e7aa57ce877194747cf5b6837133252e7f49e2
Author: Eliot Courtney <edcourtney@chromium.org>
Date: Wed Sep 27 02:16:21 2017

Set surface damage on subsurface removal.

Auto-hiding the caption, for example, would sometimes leave artifacts on
the screen when it should be fully hidden.

Bug:  767308 
Change-Id: Iae24347f8735a81a0d196e1e00ceea1559211cb7
Reviewed-on: https://chromium-review.googlesource.com/674495
Commit-Queue: Eliot Courtney <edcourtney@chromium.org>
Reviewed-by: David Reveman <reveman@chromium.org>
Cr-Commit-Position: refs/heads/master@{#504549}
[modify] https://crrev.com/28e7aa57ce877194747cf5b6837133252e7f49e2/components/exo/surface.cc
[modify] https://crrev.com/28e7aa57ce877194747cf5b6837133252e7f49e2/components/exo/surface_unittest.cc

This bug appeared in M62 so might be good to merge it to M62 (not sure). The two symptoms of this bug I've observed are: 1. Sometimes auto-hide caption will leave a several pixel wide line spanning the top of the screen when it hides. 2. If you enable the red outline developer option for when Android applications lock the UI thread, it can stay on the screen for a while.

Approved for 62, but please verify a Chrome with this change makes it through the PFQ before merging back. 

This issue has been approved for a merge. Please merge the fix to any appropriate branches as soon as possible!

If all merges have been completed, please remove any remaining Merge-Approved labels from this issue.

Thanks for your time! To disable nags, add the Disable-Nags label.

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The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/c07ac15a6763e652fd8cbf4c1290275a56e293ca

commit c07ac15a6763e652fd8cbf4c1290275a56e293ca
Author: Eliot Courtney <edcourtney@chromium.org>
Date: Wed Oct 04 06:20:01 2017

Set surface damage on subsurface removal.

Auto-hiding the caption, for example, would sometimes leave artifacts on
the screen when it should be fully hidden.

(cherry picked from commit 28e7aa57ce877194747cf5b6837133252e7f49e2)

Bug:  767308 
Change-Id: Iae24347f8735a81a0d196e1e00ceea1559211cb7
Reviewed-on: https://chromium-review.googlesource.com/674495
Commit-Queue: Eliot Courtney <edcourtney@chromium.org>
Reviewed-by: David Reveman <reveman@chromium.org>
Cr-Original-Commit-Position: refs/heads/master@{#504549}
Reviewed-on: https://chromium-review.googlesource.com/696866
Reviewed-by: Tomasz Mikolajewski <mtomasz@chromium.org>
Cr-Commit-Position: refs/branch-heads/3202@{#575}
Cr-Branched-From: fa6a5d87adff761bc16afc5498c3f5944c1daa68-refs/heads/master@{#499098}
[modify] https://crrev.com/c07ac15a6763e652fd8cbf4c1290275a56e293ca/components/exo/surface.cc
[modify] https://crrev.com/c07ac15a6763e652fd8cbf4c1290275a56e293ca/components/exo/surface_unittest.cc