Possibly related to  bug 849356 .

https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/1085898
https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/1085899

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/tools/depot_tools/+/9ac59795af3a5a7a3dac572867d2cfce7dc6c21e

commit 9ac59795af3a5a7a3dac572867d2cfce7dc6c21e
Author: Nodir Turakulov <nodir@google.com>
Date: Mon Jun 04 20:14:24 2018

Fix buildbucket bug filing instructions

Use Infra>Platform>Buildbucket component, not Infra-BuildBucket label.

R=qyearsley

Bug:  849361 
Change-Id: I27706d93097a20c6927ffa5405550bb63aa519dd
Reviewed-on: https://chromium-review.googlesource.com/1085898
Reviewed-by: Quinten Yearsley <qyearsley@chromium.org>
Commit-Queue: Nodir Turakulov <nodir@chromium.org>

[modify] https://crrev.com/9ac59795af3a5a7a3dac572867d2cfce7dc6c21e/git_cl.py

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/tools/depot_tools/+/23d75d2db4444e3e61c91dd78a09c977c88a3083

commit 23d75d2db4444e3e61c91dd78a09c977c88a3083
Author: Nodir Turakulov <nodir@google.com>
Date: Mon Jun 04 20:14:35 2018

[git-cl-try] Handle absence of builds

If there are no builds in build search response, the response is {}.
Handle this case.

R=qyearsley

Bug:  849361 
Change-Id: I9f0472e140698a1d1c5b98b301bc562ac457785b
Reviewed-on: https://chromium-review.googlesource.com/1085899
Reviewed-by: Quinten Yearsley <qyearsley@chromium.org>
Commit-Queue: Nodir Turakulov <nodir@chromium.org>

[modify] https://crrev.com/23d75d2db4444e3e61c91dd78a09c977c88a3083/git_cl.py

> Possibly related to  bug 849356 .
it is related. This bug is the cause of  bug 849356 

smut@, I suspect the recent switch to webapp2 adapter changed the response from {"builds":[]} to {}, but now I cannot check. If that's the case, it may be a serious change in the API so we may have to include this in the PSA/readme and warn that clients might have to update their code. I hope, this is not the case. Please verify.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/c8f930d85555655f25d3ac89a4b87eb272d23796

commit c8f930d85555655f25d3ac89a4b87eb272d23796
Author: depot-tools-chromium-autoroll <depot-tools-chromium-autoroll@skia-buildbots.google.com.iam.gserviceaccount.com>
Date: Tue Jun 05 01:30:00 2018

Roll src/third_party/depot_tools 518bb68..23d75d2 (2 commits)

https://chromium.googlesource.com/chromium/tools/depot_tools.git/+log/518bb68..23d75d2


git log 518bb68..23d75d2 --date=short --no-merges --format='%ad %ae %s'
2018-06-04 nodir@google.com [git-cl-try] Handle absence of builds
2018-06-04 nodir@google.com Fix buildbucket bug filing instructions


Created with:
  gclient setdep -r src/third_party/depot_tools@23d75d2

The AutoRoll server is located here: https://depot-tools-chromium-roll.skia.org

Documentation for the AutoRoller is here:
https://skia.googlesource.com/buildbot/+/master/autoroll/README.md

If the roll is causing failures, please contact the current sheriff, who should
be CC'd on the roll, and stop the roller if necessary.



BUG= chromium:849361 , chromium:849361 
TBR=agable@chromium.org

Change-Id: Ie899f8051bb2940e4345f825fb0482ac52b489d2
Reviewed-on: https://chromium-review.googlesource.com/1086027
Reviewed-by: depot-tools-chromium-autoroll <depot-tools-chromium-autoroll@skia-buildbots.google.com.iam.gserviceaccount.com>
Commit-Queue: depot-tools-chromium-autoroll <depot-tools-chromium-autoroll@skia-buildbots.google.com.iam.gserviceaccount.com>
Cr-Commit-Position: refs/heads/master@{#564332}
[modify] https://crrev.com/c8f930d85555655f25d3ac89a4b87eb272d23796/DEPS

What endpoint is this for?

git cl try-results makes requests to the path /_ah/api/buildbucket/v1/search on buildbucket (https://cs.chromium.org/chromium/tools/depot_tools/git_cl.py?l=557)

Looks like search (in fetch_try_jobs). I just ran a search expecting 0 results.

From the adapter we get:
{
}

From Cloud Endpoints v1 we get:
{
 "kind": "buildbucket#resourcesItem",
 "etag": "\"3ZW5-2XHELj2Wm1cpXWt-FqpT1I/2EANWYnpnxDCsekD8jwrG6ScUy4\""
}

Because "kind" and "etag" were inserted into the response it appears non-empty from git cl try-results's perspective.

I checked some other APIs and some other services, they all have "kind": "<servicename>#resourceItem". I suppose we could just have the adapter inject this into the response when the status is 200 OK. That seems to be what Cloud Endpoints v1 does.