A couple of follow-ups here:

 - the process has changed a bit since qyearsley set up the --root-layer-scrolls bot, and the new bot will no longer be running in an existing pool. thinking 1-2 machines for this -- would that be ok?
 - are you ok w/ a name like "linux-blink-gen-property-trees"?

oh, and also: would a CI bot be useful here?

Is that because swarming uses a giant olympic-sized pool of machines?

"linux-blink-gen-property-trees" sounds great!

Is a CI bot a bot that constantly runs on a waterfall? If so, I don't think it's really necessary because all code being written for this project is greenfield. The CQ bot will prevent people working on this code from checking in code that breaks existing passing layout tests. A CI bot would prevent people not working on this code from breaking us, but I think that'll be rare.

No (though it does); it's because of the buildbot->luci switch, if you're familiar w/ that. We want to have groups of builders share pools of machines, but there are blockers for doing so in luci.

yep, that's a CI bot. CI wouldn't necessarily prevent anything, but it'd let y'all see the current state of the tests on master. if you just want the trybot, that's fine.

Yeah, I think just a trybot will be good for now. Thanks!

The following revision refers to this bug:
  https://chrome-internal.googlesource.com/infradata/config/+/4314d1c1848d2813f846c572a615279db21b172e

commit 4314d1c1848d2813f846c572a615279db21b172e
Author: John Budorick <jbudorick@google.com>
Date: Tue May 08 21:41:01 2018

The following revision refers to this bug:
  https://chrome-internal.googlesource.com/infradata/config/+/54182a6f18204025218d6efb5c20e4ac329f3782

commit 54182a6f18204025218d6efb5c20e4ac329f3782
Author: John Budorick <jbudorick@google.com>
Date: Tue May 08 23:57:14 2018

When I try running this bot, I just get a purple box:
Cq-Include-Trybots: master.tryserver.blink:linux-blink-gen-property-trees
https://chromium-review.googlesource.com/c/chromium/src/+/1053766

#9: yep, it's not set up yet. will update the status of this bug when it is.

src/ changes: https://chromium-review.googlesource.com/c/chromium/src/+/1060640
build/ changes: https://chromium-review.googlesource.com/c/chromium/tools/build/+/1049947

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/6650ef161364315fa419ef53a8a1a3d03a900e51

commit 6650ef161364315fa419ef53a8a1a3d03a900e51
Author: John Budorick <jbudorick@chromium.org>
Date: Wed May 16 23:33:17 2018

Add compile, test, buildbucket, and milo configs for gen-property-trees trybot.

Bug:  838354 
Change-Id: Icf745b379da838efcddf58a723c03fa71ad814c4
Reviewed-on: https://chromium-review.googlesource.com/1060640
Commit-Queue: John Budorick <jbudorick@chromium.org>
Reviewed-by: Philip Rogers <pdr@chromium.org>
Reviewed-by: Stephen Martinis <martiniss@chromium.org>
Cr-Commit-Position: refs/heads/master@{#559337}
[modify] https://crrev.com/6650ef161364315fa419ef53a8a1a3d03a900e51/infra/config/global/cr-buildbucket.cfg
[modify] https://crrev.com/6650ef161364315fa419ef53a8a1a3d03a900e51/infra/config/global/luci-milo.cfg
[modify] https://crrev.com/6650ef161364315fa419ef53a8a1a3d03a900e51/testing/buildbot/chromium.fyi.json
[modify] https://crrev.com/6650ef161364315fa419ef53a8a1a3d03a900e51/testing/buildbot/test_suite_exceptions.pyl
[modify] https://crrev.com/6650ef161364315fa419ef53a8a1a3d03a900e51/testing/buildbot/waterfalls.pyl
[modify] https://crrev.com/6650ef161364315fa419ef53a8a1a3d03a900e51/tools/mb/mb_config.pyl

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/tools/build/+/283456931d2ef45cbd9833765b03b47b1a127fa2

commit 283456931d2ef45cbd9833765b03b47b1a127fa2
Author: John Budorick <jbudorick@chromium.org>
Date: Thu May 17 00:02:49 2018

Recipe config for gen-property-trees ci + try bots.

(Not spinning up a CI bot at this time, though.)

Bug:  838354 
Change-Id: I51f3c3af3659d9f238ca459d9641862e279c33dd
Reviewed-on: https://chromium-review.googlesource.com/1049947
Reviewed-by: Stephen Martinis <martiniss@chromium.org>
Commit-Queue: John Budorick <jbudorick@chromium.org>

[modify] https://crrev.com/283456931d2ef45cbd9833765b03b47b1a127fa2/tests/masters_recipes_test.py
[modify] https://crrev.com/283456931d2ef45cbd9833765b03b47b1a127fa2/scripts/slave/recipe_modules/chromium_tests/trybots.py
[modify] https://crrev.com/283456931d2ef45cbd9833765b03b47b1a127fa2/scripts/slave/recipe_modules/chromium_tests/chromium_fyi.py

try bot is up & triggerable via the gerrit ui or `git cl try -B luci.chromium.try -b linux-bling-gen-property-trees`

re #14: s/bling/blink/

If you're trying to use Cq-Include-Trybots, you'll likely need to do something like

  Cq-Include-Trybots: luci.chromium.try:linux-blink-gen-property-trees

though I haven't explicitly tried that flow, unlike the other two.

This is failing to run the layout tests. The error is:
----------------
15:12:36.266 27763 Using port 'linux-trusty'
15:12:36.266 27763 Test configuration: <trusty, x86_64, release>
15:12:36.266 27763 View the test results at file:///b/s/w/ioaC4h1x/layout-test-results/results.html
15:12:36.266 27763 Using random order with seed: 4
15:12:36.266 27763 Baseline search path: linux -> win -> enable-blink-gen-property-trees -> linux -> win -> generic
15:12:36.266 27763 Using Release build
15:12:36.266 27763 Pixel tests enabled
15:12:36.266 27763 Regular timeout: 6000, slow test timeout: 30000
15:12:36.267 27763 Command line: /b/s/w/ir/out/Release/content_shell --enable-blink-gen-property-trees --run-web-tests --ignore-certificate-errors-spki-list=Nxvaj3+bY3oVrTc+Jp7m3E3sB1n3lXtnMDCyBsqEXiY= --user-data-dir --enable-crash-reporter --crash-dumps-dir=/b/s/w/ir/out/Release/crash-dumps -
15:12:36.267 27763 
15:12:36.267 27763 Collecting tests ...
15:12:36.267 27763 Generating MANIFEST.json for web-platform-tests ...
15:12:36.267 27763 Manifest not found, copying from base "/b/s/w/ir/third_party/WebKit/LayoutTests/external/WPT_BASE_MANIFEST.json".
15:12:43.682 27763 "python /b/s/w/ir/third_party/blink/tools/blinkpy/third_party/wpt/wpt/wpt manifest --work --tests-root /b/s/w/ir/third_party/WebKit/LayoutTests/external/wpt" took 7.05s
15:12:43.682 27763 Manifest generation completed.
15:12:43.682 27763 Completed generating manifest.
15:12:43.682 27763 Collecting tests ...
15:12:53.427 27763 Parsing expectations ...
15:13:18.989 27763 Found 78857 tests; running 3877, skipping 74980.
15:13:18.989 27763 Checking build ...
15:13:18.990 27763 Unable to find test driver
15:13:18.990 27763     at /b/s/w/ir/out/Release/content_shell
15:13:18.990 27763 For complete Linux build requirements, please see:
15:13:18.990 27763 
15:13:18.990 27763     https://chromium.googlesource.com/chromium/src/+/master/docs/linux_build_instructions.md
15:13:18.990 27763 Build check failed
----------------


I confirmed that content shell is being built & linked like on other bots. Could this binary not be getting copied to the machine running the test?

Here's the failing run:
https://ci.chromium.org/p/chromium/builders/luci.chromium.try/linux-blink-gen-property-trees/6

I kicked this off via the command line. Same error when using Cq-Include-Trybots.

Interesting.

looking for out/Release/content_shell from a debug build. X(

fix is https://chromium-review.googlesource.com/c/chromium/src/+/1065146

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/4779520d87582ea767506e1e95aed1b1fb13079a

commit 4779520d87582ea767506e1e95aed1b1fb13079a
Author: John Budorick <jbudorick@chromium.org>
Date: Fri May 18 01:30:35 2018

Add --debug to linux-blink-gen-property-trees command line.

TBR=pdr@chromium.org

Bug:  838354 
Change-Id: If959a73997c82edd7e214ef4657799b64bb12641
Reviewed-on: https://chromium-review.googlesource.com/1065146
Reviewed-by: John Budorick <jbudorick@chromium.org>
Commit-Queue: John Budorick <jbudorick@chromium.org>
Cr-Commit-Position: refs/heads/master@{#559762}
[modify] https://crrev.com/4779520d87582ea767506e1e95aed1b1fb13079a/testing/buildbot/chromium.fyi.json
[modify] https://crrev.com/4779520d87582ea767506e1e95aed1b1fb13079a/testing/buildbot/test_suite_exceptions.pyl

It works! Thank you!!