I think that https://crrev.com/c/1237422 should get these going on *-tot-chrome-pfq-informational.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromiumos/third_party/autotest/+/d6338ef48302fa52b5cfa4a2e231f010ec30b1fa

commit d6338ef48302fa52b5cfa4a2e231f010ec30b1fa
Author: Daniel Erat <derat@chromium.org>
Date: Fri Sep 21 07:51:19 2018

autotest: Split tast.informational into smaller pieces.

Split the tast.informational server test, which currently
runs informational Tast tests as part of the bvt-perbuild
suite, into separate tast.informational-android, -chrome,
and -system tests.

All three tests still run as part of bvt-perbuild, but
-android and -chrome also run as part of the
chrome-informational suite. This should result in
tot-chrome-pfq-informational builders running informational
Tast tests against ToT Chrome.

BUG= chromium:887575 
TEST=passed all three expressions to "tast list" and
     verified that they match the expected tests

Change-Id: I1448e29cab5b605fa75728c47b5fbe717f938359
Reviewed-on: https://chromium-review.googlesource.com/1237422
Commit-Ready: Dan Erat <derat@chromium.org>
Tested-by: Dan Erat <derat@chromium.org>
Reviewed-by: Ilja H. Friedel <ihf@chromium.org>

[copy] https://crrev.com/d6338ef48302fa52b5cfa4a2e231f010ec30b1fa/server/site_tests/tast/control.informational-chrome
[rename] https://crrev.com/d6338ef48302fa52b5cfa4a2e231f010ec30b1fa/server/site_tests/tast/control.informational-system
[copy] https://crrev.com/d6338ef48302fa52b5cfa4a2e231f010ec30b1fa/server/site_tests/tast/control.informational-android

I think that you can see these results now at e.g. http://stainless/search?view=matrix&row=test&col=build&first_date=2018-09-15&last_date=2018-09-21&builder_name=-tot-chrom.*-pfq-informational%24&test=%5Etast%5C..*%5C.&exclude_cts=false&exclude_not_run=false&exclude_non_release=false&exclude_au=true&exclude_acts=true&exclude_retried=true&exclude_non_production=false

Will this turn the chrome ToT pfq informational builders red if the Tast test fails?

(chrome-informational won't block PFQ if it turns red, which is fine with me for Mash tests.)

No, unfortunately (assuming that you want that to happen...). There are more flaky informational tests than I'd like (and the whole point of the "informational" attribute is that failures don't turn anything red).

I'm hopeful that we'll have a better alerting solution at some point that makes it easier to learn about failures as soon as they occur. In the meantime, would it help if stainless-alert let you specify a builder regexp?

Hrm. Some way to get separate notifications of ToT failures would be nice. (e.g. run a cronjob every hour to look for ToT failures, and another one for nightly per-build summaries)

The following revision refers to this bug:
  https://chrome-internal.googlesource.com/chromeos/chromeos-admin/+/2fe36f5490ff84bd37b2f1e859b9c52c24b749db

commit 2fe36f5490ff84bd37b2f1e859b9c52c24b749db
Author: Daniel Erat <derat@chromium.org>
Date: Sat Sep 22 00:38:47 2018