The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/31af26ea9a369c395d292e5ea05885a936fbecd4

commit 31af26ea9a369c395d292e5ea05885a936fbecd4
Author: Peter Collingbourne <pcc@chromium.org>
Date: Wed Jun 06 00:33:31 2018

Use swarming on ToTLinuxThinLTO.

The lack of swarming was the most likely cause of mysterious test
failures that weren't affecting any other builder.

Bug:  849868 
Change-Id: I6ee8b78886dce01a319062b3d6526381bb25ecf3
Reviewed-on: https://chromium-review.googlesource.com/1087818
Reviewed-by: Nico Weber <thakis@chromium.org>
Commit-Queue: Peter Collingbourne <pcc@chromium.org>
Cr-Commit-Position: refs/heads/master@{#564737}
[modify] https://crrev.com/31af26ea9a369c395d292e5ea05885a936fbecd4/testing/buildbot/chromium.clang.json
[modify] https://crrev.com/31af26ea9a369c395d292e5ea05885a936fbecd4/testing/buildbot/waterfalls.pyl

Recently it seems to be failed gl_unittests that's failing, but the other tests pass.

I'm trying to fix that in https://chromium-review.googlesource.com/c/chromium/src/+/1089589

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/2125f8979046e10bfa7c40827252a69e3d60e6a6

commit 2125f8979046e10bfa7c40827252a69e3d60e6a6
Author: Nico Weber <thakis@chromium.org>
Date: Fri Jun 08 23:19:53 2018

Use chromium_linux_and_gl_gtests on fewer bots.

"Out of Process Profiling Linux" used chromium_linux_and_gl_gtests and then
removed of the suites added by _and_gl via test_suite_exceptions again.
Instead, just use regular chromium_linux_gtests for it. No behavior change.

"ToTLinuxThinLTO" used the _and_gl version and removed gl_tests again.
It didn't remove gl_unittests, but that one was failing on it. So just
use chromium_linux_gtests here too.

"ToTLinuxUBSanVptr" and "UBSanVptr Linux" were removing gl_tests (but not
gl_unittests) via the exceptions file despite not (yet?) using the _and_gl
test list, so remove these unused exceptions.

Add a comment explaining why interactive_ui_tests doesn't run on the ubsan
bots (probably it should run there, with just the few failing tests disabled).

Bug: 843511, 849868 
Change-Id: Ifd6397529fce300ef989f3a637f7ec48bd784175
Reviewed-on: https://chromium-review.googlesource.com/1093570
Reviewed-by: Peter Collingbourne <pcc@chromium.org>
Reviewed-by: Kenneth Russell <kbr@chromium.org>
Cr-Commit-Position: refs/heads/master@{#565773}
[modify] https://crrev.com/2125f8979046e10bfa7c40827252a69e3d60e6a6/testing/buildbot/chromium.clang.json
[modify] https://crrev.com/2125f8979046e10bfa7c40827252a69e3d60e6a6/testing/buildbot/test_suite_exceptions.pyl
[modify] https://crrev.com/2125f8979046e10bfa7c40827252a69e3d60e6a6/testing/buildbot/waterfalls.pyl

Bot is green now.