ReattachDevToolsWindow very occasionally fails, disabling it for Mac.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/b4489c4d019b9a4c45fb5138db7ee9ddcb681bfc

commit b4489c4d019b9a4c45fb5138db7ee9ddcb681bfc
Author: Ramin Halavati <rhalavati@chromium.org>
Date: Thu Jun 14 09:06:16 2018

Disable failing test on Mac: ReattachDevToolsWindow

BrowserTest.ReattachDevToolsWindow occasionally fails on Mac 10.11.

Bug: 852697
Change-Id: Ibd94a9b94d7963825c42dbe50fb8c72097409da0
TBR: ellyjones@chromium.org
Reviewed-on: https://chromium-review.googlesource.com/1100465
Reviewed-by: Ramin Halavati <rhalavati@chromium.org>
Commit-Queue: Ramin Halavati <rhalavati@chromium.org>
Cr-Commit-Position: refs/heads/master@{#567201}
[modify] https://crrev.com/b4489c4d019b9a4c45fb5138db7ee9ddcb681bfc/chrome/browser/ui/browser_browsertest.cc

Adding test author to CC.

Flakiness dashboard link:
https://test-results.appspot.com/dashboards/flakiness_dashboard.html#testType=browser_tests&tests=ReattachDevToolsWindow

Looks like the earliest failure was at 6/12/2018 7:47:38 PM GMT+2, and after that it mostly failed. It's failing only on 10.11 and 10.12 though, both 10.10 and 10.13 are fine?!

There were also some pretty big general problems with browser_tests on Mac recently [1], maybe this is just part of that?

[1] https://groups.google.com/a/chromium.org/d/topic/chromium-dev/dnwMoZfTyos/discussion

reassing to treib to re-enable/follow-up on? Feel free to delegate. Removing from the sheriff queue.

 Issue 852326  has been merged into this issue.

While I did write that test a while back, I'm not actually very familiar with this code, or with Mac in general. Over to Mac experts who can hopefully help or triage further.