The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/3970043f82725b9f6b2f9eeab6f7a6e55d8cc290

commit 3970043f82725b9f6b2f9eeab6f7a6e55d8cc290
Author: Jeff Carpenter <jeffcarp@chromium.org>
Date: Fri Jun 09 03:40:42 2017

[WPT Export] Don't create a PR from a Gerrit CL if no reviewers yet

Bug:  727914 
Change-Id: I4e850f4bed9de1cff0e8a8d465fa178aadd052d1
Reviewed-on: https://chromium-review.googlesource.com/528453
Reviewed-by: Quinten Yearsley <qyearsley@chromium.org>
Commit-Queue: Jeff Carpenter <jeffcarp@chromium.org>
Cr-Commit-Position: refs/heads/master@{#478186}
[modify] https://crrev.com/3970043f82725b9f6b2f9eeab6f7a6e55d8cc290/third_party/WebKit/Tools/Scripts/webkitpy/w3c/gerrit.py
[modify] https://crrev.com/3970043f82725b9f6b2f9eeab6f7a6e55d8cc290/third_party/WebKit/Tools/Scripts/webkitpy/w3c/test_exporter.py
[modify] https://crrev.com/3970043f82725b9f6b2f9eeab6f7a6e55d8cc290/third_party/WebKit/Tools/Scripts/webkitpy/w3c/test_exporter_unittest.py

Created a CL to verify this:
https://chromium-review.googlesource.com/c/530191/

The CL didn't work >:(
https://github.com/w3c/web-platform-tests/pull/6208

Similar to  issue 738891 , should perhaps be fixed as one?

The Gerrit API's ChangeInfo object returns a work_in_progress field, which could be useful in fixing this:
https://gerrit-review.googlesource.com/Documentation/rest-api-changes.html#change-info

 Issue 738891  has been merged into this issue.

So there are two boolean flags on ChangeInfo we could use:

"work_in_progress"
"has_review_started"

I'm not sure in what cases these can differ, but I'm going to go ahead and make a CL that relies on "has_review_started," since that better approximates the intent behind this issue.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/62e0417223f6821f7ddb849abb5e3b2f864ec0d9

commit 62e0417223f6821f7ddb849abb5e3b2f864ec0d9
Author: Jeff Carpenter <jeffcarp@chromium.org>
Date: Thu Jul 06 19:51:56 2017

[WPT Export] Prevent PRs from WIP CLs from being created

Originally we were relying on a CL's reviewer list to prevent creating
upstream PRs for CLs without reviewers, however in practice that hasn't
been working. I believe using the ChangeInfo property has_started_review
will be a more solid solution.

Bug:  727914 
Change-Id: Ibc2e06d46ba3a16bbceda3a271b675769b040c68
Reviewed-on: https://chromium-review.googlesource.com/559836
Commit-Queue: Jeff Carpenter <jeffcarp@chromium.org>
Reviewed-by: Quinten Yearsley <qyearsley@chromium.org>
Cr-Commit-Position: refs/heads/master@{#484716}
[modify] https://crrev.com/62e0417223f6821f7ddb849abb5e3b2f864ec0d9/third_party/WebKit/Tools/Scripts/webkitpy/w3c/gerrit.py
[modify] https://crrev.com/62e0417223f6821f7ddb849abb5e3b2f864ec0d9/third_party/WebKit/Tools/Scripts/webkitpy/w3c/test_exporter.py
[modify] https://crrev.com/62e0417223f6821f7ddb849abb5e3b2f864ec0d9/third_party/WebKit/Tools/Scripts/webkitpy/w3c/test_exporter_unittest.py

Verified that the above crrev.com/c/559836 fixes this. See in logs:
https://luci-logdog.appspot.com/v/?s=chromium%2Fbb%2Fchromium.infra.cron%2Fwpt-exporter%2F27001%2F%2B%2Frecipes%2Fsteps%2FExport_Chromium_commits_and_in-flight_CLs_to_WPT%2F0%2Fstdout