target extensions_browsertests are flaking, test cases 

ShellApiTest.LoadApp (first failure https://ci.chromium.org/p/chromium/builders/luci.chromium.ci/Mac%20ASan%2064%20Tests%20%281%29/43059)
ShellRuntimeApiTest.RuntimeReloadApp (first failure) https://ci.chromium.org/p/chromium/builders/luci.chromium.ci/Mac%20ASan%2064%20Tests%20%281%29/43064

I think it's likely the same commit right before 2018-08-20 11:12 AM (PDT) that caused both to start flaking, going to disable both.

Can we get a better bisect on the potential culprit?

It's better to revert new changes which cause instability like this. Rather than disable tests

This was caused by: https://chromium-review.googlesource.com/c/chromium/src/+/1095815

mohsen@ is working on a fix: http://crrev.com/c/1182282

 Issue 876047  has been merged into this issue.

Thanks jonross!

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/3ccabcfd8c127fc7e45d1640e836b874eaa26585

commit 3ccabcfd8c127fc7e45d1640e836b874eaa26585
Author: Mohsen Izadi <mohsen@chromium.org>
Date: Tue Aug 21 19:32:13 2018

Fix flakiness caused by crrev/584455

During shut down, HostGpuMemoryBufferManager singleton instance in
content is destroyed before winding down the IO thread. Probably after
that and before IO thread is shut down completely, there are GPU clients
that might try to create GPU memory buffers. Ignore those requests.

BUG= 876327 

Cq-Include-Trybots: luci.chromium.try:android_optional_gpu_tests_rel
Change-Id: I53854f451129693a5167fe0bb21cd9d72925b585
Reviewed-on: https://chromium-review.googlesource.com/1182282
Commit-Queue: Mohsen Izadi <mohsen@chromium.org>
Reviewed-by: kylechar <kylechar@chromium.org>
Cr-Commit-Position: refs/heads/master@{#584878}
[modify] https://crrev.com/3ccabcfd8c127fc7e45d1640e836b874eaa26585/components/viz/host/gpu_client.cc