+jbudorick and bpastene as the Android infra folks.

dewittj@ - could you provide more details for your request? 
It sounds like a CI (aka "waterfall") builder be sufficient. My understanding is, you don't need it on CQ at this stage, correct?

I will comment on example:

https://bugs.chromium.org/p/chromium/issues/detail?id=895593

Some other CL was tested without "use_jumbo_build=true", was breaking Jumbo compilation and was put into code, 

we need to eliminate such cases by trying making compilation with Jumbo for every CL in any moment before submitting.

Nothing more is required.

...it means (if I understand correctly) - CI is enough, CQ not required.

> making compilation with Jumbo for every CL in any moment before submitting

That sounds like you want pre-submit coverage (ensuring no CL lands that breaks the jumbo android build). That's CQ.

CI is post-submit coverage. (CLs that break the jumbo android build can still land, but would theoretically be reverted shortly after by sheriffs.)

We can pretty easily add post-submit/CI coverage, but adding pre-submit/CQ is a bit more difficult & costly. We try to avoid adding CQ bots unless it would catch enough breakages to warrant doing so.

We don't currently have either CQ or CI coverage for jumbo on android. I agree that we should start with a CI config, at least.

Alright, I can get the CI bot up.

The following revision refers to this bug:
  https://chrome-internal.googlesource.com/infradata/config/+/8cbb9525a98da035df2dec56abbb359a34f0f79d

commit 8cbb9525a98da035df2dec56abbb359a34f0f79d
Author: Ben Pastene <bpastene@chromium.org>
Date: Fri Oct 19 18:37:45 2018

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/f0536f4628fc12b899481c592e7672740b871981

commit f0536f4628fc12b899481c592e7672740b871981
Author: Ben Pastene <bpastene@chromium.org>
Date: Fri Oct 19 19:21:52 2018

Add src-side configs for android-jumbo-rel CI bot.

Bug:  896410 
Change-Id: I1b2825dfe67c7895b1152c854303d79b9d4a20fb
Reviewed-on: https://chromium-review.googlesource.com/c/1292049
Reviewed-by: Stephen Martinis <martiniss@chromium.org>
Commit-Queue: Ben Pastene <bpastene@chromium.org>
Cr-Commit-Position: refs/heads/master@{#601250}
[modify] https://crrev.com/f0536f4628fc12b899481c592e7672740b871981/infra/config/global/cr-buildbucket.cfg
[modify] https://crrev.com/f0536f4628fc12b899481c592e7672740b871981/infra/config/global/luci-milo.cfg
[modify] https://crrev.com/f0536f4628fc12b899481c592e7672740b871981/infra/config/global/luci-scheduler.cfg
[modify] https://crrev.com/f0536f4628fc12b899481c592e7672740b871981/testing/buildbot/chromium.android.json
[modify] https://crrev.com/f0536f4628fc12b899481c592e7672740b871981/testing/buildbot/waterfalls.pyl
[modify] https://crrev.com/f0536f4628fc12b899481c592e7672740b871981/tools/mb/mb_config.pyl

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/tools/build/+/652545e75cdf9924d83b834f06b09fb57acb15e6

commit 652545e75cdf9924d83b834f06b09fb57acb15e6
Author: Ben Pastene <bpastene@chromium.org>
Date: Fri Oct 19 19:22:25 2018

Add recipe config for android-jumbo-rel CI bot.

R=jbudorick, martiniss

Bug:  896410 
Change-Id: Idd879e203b1059a44572ac32fe20f30203cc69fb
Reviewed-on: https://chromium-review.googlesource.com/c/1292089
Commit-Queue: Ben Pastene <bpastene@chromium.org>
Commit-Queue: Stephen Martinis <martiniss@chromium.org>
Auto-Submit: Ben Pastene <bpastene@chromium.org>
Reviewed-by: Stephen Martinis <martiniss@chromium.org>

[modify] https://crrev.com/652545e75cdf9924d83b834f06b09fb57acb15e6/scripts/slave/recipe_modules/chromium_tests/chromium_android.py

CI bot up at https://luci-milo.appspot.com/p/chromium/builders/luci.chromium.ci/android-jumbo-rel

PTAL at cycle time, GN args, compile targets (it currently builds 'all') and LMK if you need anything tweaked. Thanks.

The CI bot has been up for a while and looks good. I'm closing this out.

If you'd also like it in the CQ, feel free to reopen and we can discuss that.

I'm confused - it looks, that we have next Jumbo bug: https://bugs.chromium.org/p/chromium/issues/detail?id=903460