Findit identified the culprit r579853 with confidence 70.0% in the config "chromium.win / Win7 (32) Tests"
based on the flakiness trend:

https://findit-for-me.appspot.com/waterfall/flake?key=ag9zfmZpbmRpdC1mb3ItbWVypwELEhdNYXN0ZXJGbGFrZUFuYWx5c2lzUm9vdCJxY2hyb21pdW0ud2luL1dpbjcgKDMyKSBUZXN0cy8zNjQyNi9icm93c2VyX3Rlc3RzL1RtRkRiRUp5YjNkelpYSlVaWE4wVUc1aFkyeFRkV0o2WlhKdkxsQnVZV05zUlhKeWIzSklZVzVrYkdsdVp3PT0MCxITTWFzdGVyRmxha2VBbmFseXNpcxgBDA

If the culprit above is wrong, please file a bug using this link and hit submit:
https://bugs.chromium.org/p/chromium/issues/entry?status=Unconfirmed&labels=Pri-1,Test-Findit-Wrong&components=Tools%3ETest%3EFindit%3EFlakiness&summary=%5BFindit%5D%20Flake%20Analyzer%20-%20Wrong%20result%20for%20NaClBrowserTestPnaclSubzero.PnaclErrorHandling&comment=Link%20to%20Analysis%3A%20https://findit-for-me.appspot.com/waterfall/flake?key=ag9zfmZpbmRpdC1mb3ItbWVypwELEhdNYXN0ZXJGbGFrZUFuYWx5c2lzUm9vdCJxY2hyb21pdW0ud2luL1dpbjcgKDMyKSBUZXN0cy8zNjQyNi9icm93c2VyX3Rlc3RzL1RtRkRiRUp5YjNkelpYSlVaWE4wVUc1aFkyeFRkV0o2WlhKdkxsQnVZV05zUlhKeWIzSklZVzVrYkdsdVp3PT0MCxITTWFzdGVyRmxha2VBbmFseXNpcxgBDA

Automatically posted by the findit-for-me app (https://goo.gl/Ot9f7N).

thomasanderson@
your CL doesn't seem related, but I didn't notice any other candidates. Please check just in case.

I will disable the test in the meantime.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/5b35992cbe828ddf356ab3296ef9106f01a779c3

commit 5b35992cbe828ddf356ab3296ef9106f01a779c3
Author: Christos Froussios <cfroussios@chromium.org>
Date: Thu Aug 02 16:28:34 2018

Disable NaClBrowserTestPnaclSubzero.PnaclErrorHandling on windows

It is flaky

TBR=bradnelson@chromium.org

Bug:  870309 
Change-Id: I8a55fdaae7091b0dc32247527d50a35510e7a4bf
Reviewed-on: https://chromium-review.googlesource.com/1160542
Reviewed-by: Christos Froussios <cfroussios@chromium.org>
Commit-Queue: Christos Froussios <cfroussios@chromium.org>
Cr-Commit-Position: refs/heads/master@{#580211}
[modify] https://crrev.com/5b35992cbe828ddf356ab3296ef9106f01a779c3/chrome/test/nacl/nacl_browsertest.cc

bradnelson@ to bug owner for triage.

Removing sheriff label.

I think that CL shouldn't have any effect on the Windows build