https://chromium-review.googlesource.com/c/chromium/src/+/927882 removed parts of linux_chromium_ubsan_rel_ng, but as the CL description says the bot already didn't exist anymore at this point.

https://chromium-review.googlesource.com/c/chromium/tools/build/+/927868 removed the bot, because it hadn't been updated to point to chromium.clang instead of chromium.fyi after all the clang bots moved over. I wish I had been cc'd on that review, then I could've pointed that out.

I'll revert the ubsan bits of https://chromium-review.googlesource.com/c/chromium/tools/build/+/927868 and make the bot point to .clang instead and then I'll revert the ubsan bits of https://chromium-review.googlesource.com/c/chromium/src/+/927882

(the win_clang_dbg etc bots are no longer needed now that that switch has stuck.)

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/tools/build/+/e4c52ab421b7da4573c1c727654e65040dff1618

commit e4c52ab421b7da4573c1c727654e65040dff1618
Author: Nico Weber <thakis@chromium.org>
Date: Sat Jun 23 02:40:10 2018

Fix and revive linux_chromium_ubsan_rel_ng bot.

Bug:  855269 
Change-Id: I18b6728f1354ef0335171a94b417233a82d949c9
Reviewed-on: https://chromium-review.googlesource.com/1112042
Reviewed-by: Kenneth Russell <kbr@chromium.org>
Reviewed-by: Dirk Pranke <dpranke@chromium.org>
Commit-Queue: Nico Weber <thakis@chromium.org>

[modify] https://crrev.com/e4c52ab421b7da4573c1c727654e65040dff1618/masters/master.tryserver.chromium.linux/slaves.cfg
[modify] https://crrev.com/e4c52ab421b7da4573c1c727654e65040dff1618/scripts/slave/recipe_modules/chromium_tests/trybots.py
[modify] https://crrev.com/e4c52ab421b7da4573c1c727654e65040dff1618/masters/master.tryserver.chromium.linux/master.cfg

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/f1be51540a087f573e76186c63cc1596df570693

commit f1be51540a087f573e76186c63cc1596df570693
Author: Nico Weber <thakis@chromium.org>
Date: Sat Jun 23 22:47:15 2018

Revive linux_chromium_ubsan_rel_ng mb config.

Bug:  855269 
Change-Id: I8ab4534f2ede8c0b8d2f3348309046ee0de9d164
Reviewed-on: https://chromium-review.googlesource.com/1112043
Reviewed-by: Dirk Pranke <dpranke@chromium.org>
Commit-Queue: Nico Weber <thakis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#569910}
[modify] https://crrev.com/f1be51540a087f573e76186c63cc1596df570693/tools/mb/mb_config.pyl

It's back: https://ci.chromium.org/buildbot/tryserver.chromium.linux/linux_chromium_ubsan_rel_ng/149

Compile is broken, but that's  bug 855610 .