https://chromium-review.googlesource.com/c/chromium/src/+/837643 touched automation_apitest.cc shortly before the flakiness. Will see if it’s still flaky in a revert CL.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/66b0a700630f1b6944e7b5e224cedf800b601fcb

commit 66b0a700630f1b6944e7b5e224cedf800b601fcb
Author: Chris Pickel <sfiera@chromium.org>
Date: Fri Feb 02 11:27:20 2018

Revert "Expose reverse relationships in the automation API."

This reverts commit a55fe78f801dbf3c10f34a665bb9673393f9e494.

Reason for revert: Possible source of flakiness in AutomationApiTest.DesktopHitTestIframe

Original change's description:
> Expose reverse relationships in the automation API.
> 
> AXTree now keeps track of reverse relationships automatically,
> so take advantage of that to expose reverse relationships for
> some attributes already exposed in the automation API.
> Also add two relation attributes that are supported by Blink
> but weren't added to automation yet: details, errorMessage.
> 
> The new attributes are:
> 
> detailsFor (reverse of details)
> errorMessageFor (reverse of errorMessage)
> controlledBy (reverse of controls)
> descriptionFor (reverse of describedBy)
> flowFrom (reverse of flowTo)
> labelFor (reverse of labelledBy)
> 
> Bug:  757707 
> Cq-Include-Trybots: master.tryserver.chromium.linux:closure_compilation
> Change-Id: I112c283c87274388fc9e7e725bcc126393133e39
> TBR: michaelpg@chromium.org
> Reviewed-on: https://chromium-review.googlesource.com/837643
> Commit-Queue: Dominic Mazzoni <dmazzoni@chromium.org>
> Reviewed-by: David Tseng <dtseng@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#533819}

TBR=dmazzoni@chromium.org,dtseng@chromium.org,michaelpg@chromium.org

Bug:  757707 
Bug: 808343
Change-Id: Ie61c369e0f234eca7435ac80d056a6c10ea75a41
Reviewed-on: https://chromium-review.googlesource.com/897864
Reviewed-by: Chris Pickel <sfiera@chromium.org>
Commit-Queue: Chris Pickel <sfiera@chromium.org>
Cr-Commit-Position: refs/heads/master@{#534020}
[modify] https://crrev.com/66b0a700630f1b6944e7b5e224cedf800b601fcb/chrome/browser/extensions/api/automation/automation_apitest.cc
[modify] https://crrev.com/66b0a700630f1b6944e7b5e224cedf800b601fcb/chrome/common/extensions/api/automation.idl
[modify] https://crrev.com/66b0a700630f1b6944e7b5e224cedf800b601fcb/chrome/renderer/extensions/automation_internal_custom_bindings.cc
[modify] https://crrev.com/66b0a700630f1b6944e7b5e224cedf800b601fcb/chrome/renderer/extensions/automation_internal_custom_bindings.h
[modify] https://crrev.com/66b0a700630f1b6944e7b5e224cedf800b601fcb/chrome/renderer/resources/extensions/automation/automation_node.js
[delete] https://crrev.com/203fb1a894077184a9d4483d81958bb1c5bc9f4e/chrome/test/data/extensions/api_test/automation/sites/reverse_relations.html
[delete] https://crrev.com/203fb1a894077184a9d4483d81958bb1c5bc9f4e/chrome/test/data/extensions/api_test/automation/tests/tabs/reverse_relations.html
[delete] https://crrev.com/203fb1a894077184a9d4483d81958bb1c5bc9f4e/chrome/test/data/extensions/api_test/automation/tests/tabs/reverse_relations.js
[modify] https://crrev.com/66b0a700630f1b6944e7b5e224cedf800b601fcb/third_party/closure_compiler/externs/automation.js

Revert landed. Will watch for more flakes.

No flakes in the six builds since revert. Reassigning to dmazzoni.

Detected 5 new flakes for test/step "AutomationApiTest.DesktopHitTestIframe". To see the actual flakes, please visit https://chromium-try-flakes.appspot.com/all_flake_occurrences?key=ahVzfmNocm9taXVtLXRyeS1mbGFrZXNyMQsSBUZsYWtlIiZBdXRvbWF0aW9uQXBpVGVzdC5EZXNrdG9wSGl0VGVzdElmcmFtZQw. This message was posted automatically by the chromium-try-flakes app. Since flakiness is ongoing, the issue was moved back into Sheriff Bug Queue (unless already there).

Umm, the test is still flaky. 

- We should disable the test on ChromeOS.
- We probably should revert the last revert.
- We need to find a right owner (if dmazzoni is not).

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/6d0417c74bbc3b0d2d95ba9f98020e074b35348d

commit 6d0417c74bbc3b0d2d95ba9f98020e074b35348d
Author: Yuta Kitamura <yutak@chromium.org>
Date: Mon Feb 05 08:42:50 2018

Disable AutomationApiTest.DesktopHitTestIframe.

This test is flaky.

TBR=sfiera@chromium.org

Bug: 808343
Change-Id: Ifc59f0443804cb57f995c63e205ec204f951c28c
No-Try: true
Reviewed-on: https://chromium-review.googlesource.com/901104
Reviewed-by: Yuta Kitamura <yutak@chromium.org>
Commit-Queue: Yuta Kitamura <yutak@chromium.org>
Cr-Commit-Position: refs/heads/master@{#534349}
[modify] https://crrev.com/6d0417c74bbc3b0d2d95ba9f98020e074b35348d/chrome/browser/extensions/api/automation/automation_apitest.cc

The test is disabled, and the reland will land soon.

We need to find an owner for this (or confirm dmazzoni is the right owner).

There’s a lot of disabled flaky tests in automation_apitest.cc. Many of the linked bugs are duped to https://crbug.com/622387 (owned by dmazzoni@). I think he is the right owner.

Thanks to yutak@ for relanding; sorry to dmazzoni@ for the erroneous revert.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/91eabe3bdb99681b25c6490c57bd85a4d774f47f

commit 91eabe3bdb99681b25c6490c57bd85a4d774f47f
Author: Yuta Kitamura <yutak@chromium.org>
Date: Mon Feb 05 10:28:12 2018

Revert "Revert "Expose reverse relationships in the automation API.""

This reverts commit 66b0a700630f1b6944e7b5e224cedf800b601fcb.

Reason for revert: The revert did not fix the flakiness.

Original change's description:
> Revert "Expose reverse relationships in the automation API."
> 
> This reverts commit a55fe78f801dbf3c10f34a665bb9673393f9e494.
> 
> Reason for revert: Possible source of flakiness in AutomationApiTest.DesktopHitTestIframe
> 
> Original change's description:
> > Expose reverse relationships in the automation API.
> > 
> > AXTree now keeps track of reverse relationships automatically,
> > so take advantage of that to expose reverse relationships for
> > some attributes already exposed in the automation API.
> > Also add two relation attributes that are supported by Blink
> > but weren't added to automation yet: details, errorMessage.
> > 
> > The new attributes are:
> > 
> > detailsFor (reverse of details)
> > errorMessageFor (reverse of errorMessage)
> > controlledBy (reverse of controls)
> > descriptionFor (reverse of describedBy)
> > flowFrom (reverse of flowTo)
> > labelFor (reverse of labelledBy)
> > 
> > Bug:  757707 
> > Cq-Include-Trybots: master.tryserver.chromium.linux:closure_compilation
> > Change-Id: I112c283c87274388fc9e7e725bcc126393133e39
> > TBR: michaelpg@chromium.org
> > Reviewed-on: https://chromium-review.googlesource.com/837643
> > Commit-Queue: Dominic Mazzoni <dmazzoni@chromium.org>
> > Reviewed-by: David Tseng <dtseng@chromium.org>
> > Cr-Commit-Position: refs/heads/master@{#533819}
> 
> TBR=dmazzoni@chromium.org,dtseng@chromium.org,michaelpg@chromium.org
> 
> Bug:  757707 
> Bug: 808343
> Change-Id: Ie61c369e0f234eca7435ac80d056a6c10ea75a41
> Reviewed-on: https://chromium-review.googlesource.com/897864
> Reviewed-by: Chris Pickel <sfiera@chromium.org>
> Commit-Queue: Chris Pickel <sfiera@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#534020}

TBR=dmazzoni@chromium.org,dtseng@chromium.org,michaelpg@chromium.org,sfiera@chromium.org

# Not skipping CQ checks because original CL landed > 1 day ago.

Bug:  757707 , 808343
Change-Id: Iad79be2da3e76e68857e78758113268dceea16ed
Reviewed-on: https://chromium-review.googlesource.com/901202
Reviewed-by: Yuta Kitamura <yutak@chromium.org>
Commit-Queue: Yuta Kitamura <yutak@chromium.org>
Cr-Commit-Position: refs/heads/master@{#534360}
[modify] https://crrev.com/91eabe3bdb99681b25c6490c57bd85a4d774f47f/chrome/browser/extensions/api/automation/automation_apitest.cc
[modify] https://crrev.com/91eabe3bdb99681b25c6490c57bd85a4d774f47f/chrome/common/extensions/api/automation.idl
[modify] https://crrev.com/91eabe3bdb99681b25c6490c57bd85a4d774f47f/chrome/renderer/extensions/automation_internal_custom_bindings.cc
[modify] https://crrev.com/91eabe3bdb99681b25c6490c57bd85a4d774f47f/chrome/renderer/extensions/automation_internal_custom_bindings.h
[modify] https://crrev.com/91eabe3bdb99681b25c6490c57bd85a4d774f47f/chrome/renderer/resources/extensions/automation/automation_node.js
[add] https://crrev.com/91eabe3bdb99681b25c6490c57bd85a4d774f47f/chrome/test/data/extensions/api_test/automation/sites/reverse_relations.html
[add] https://crrev.com/91eabe3bdb99681b25c6490c57bd85a4d774f47f/chrome/test/data/extensions/api_test/automation/tests/tabs/reverse_relations.html
[add] https://crrev.com/91eabe3bdb99681b25c6490c57bd85a4d774f47f/chrome/test/data/extensions/api_test/automation/tests/tabs/reverse_relations.js
[modify] https://crrev.com/91eabe3bdb99681b25c6490c57bd85a4d774f47f/third_party/closure_compiler/externs/automation.js

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/2c1a16509753dfce11564e5c37ffe8a134a2b3dc

commit 2c1a16509753dfce11564e5c37ffe8a134a2b3dc
Author: Dominic Mazzoni <dmazzoni@chromium.org>
Date: Thu Mar 01 07:54:24 2018

Fix flakiness in AutomationApiTest.DesktopHitTestIframe

At least one issue was that the loadComplete event was sometimes being
received on a frame with an empty url.

Bug: 808343,622387
Change-Id: I7040a75c91f409ba07d3b9ad4e4598805e94b6ce
Reviewed-on: https://chromium-review.googlesource.com/938495
Reviewed-by: David Tseng <dtseng@chromium.org>
Commit-Queue: Dominic Mazzoni <dmazzoni@chromium.org>
Cr-Commit-Position: refs/heads/master@{#540097}
[modify] https://crrev.com/2c1a16509753dfce11564e5c37ffe8a134a2b3dc/chrome/browser/extensions/api/automation/automation_apitest.cc
[modify] https://crrev.com/2c1a16509753dfce11564e5c37ffe8a134a2b3dc/chrome/test/data/extensions/api_test/automation/tests/desktop/focus_iframe.js
[modify] https://crrev.com/2c1a16509753dfce11564e5c37ffe8a134a2b3dc/chrome/test/data/extensions/api_test/automation/tests/desktop/hit_test_iframe.js

Detected 4 new flakes for test/step "AutomationApiTest.DesktopHitTestIframe". To see the actual flakes, please visit https://chromium-try-flakes.appspot.com/all_flake_occurrences?key=ahVzfmNocm9taXVtLXRyeS1mbGFrZXNyMQsSBUZsYWtlIiZBdXRvbWF0aW9uQXBpVGVzdC5EZXNrdG9wSGl0VGVzdElmcmFtZQw. This message was posted automatically by the chromium-try-flakes app. Since flakiness is ongoing, the issue was moved back into Sheriff Bug Queue (unless already there).

Can this be reverted, for e.g. see failures on https://chromium-review.googlesource.com/c/chromium/src/+/936322

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/45d0a37bf6cc9b4944aa4710e241c0a81189f2b2

commit 45d0a37bf6cc9b4944aa4710e241c0a81189f2b2
Author: Karan Bhatia <karandeepb@chromium.org>
Date: Fri Mar 02 00:03:47 2018

Revert "Fix flakiness in AutomationApiTest.DesktopHitTestIframe"

This reverts commit 2c1a16509753dfce11564e5c37ffe8a134a2b3dc.

Reason for revert: This is still flaking.

Original change's description:
> Fix flakiness in AutomationApiTest.DesktopHitTestIframe
> 
> At least one issue was that the loadComplete event was sometimes being
> received on a frame with an empty url.
> 
> Bug: 808343,622387
> Change-Id: I7040a75c91f409ba07d3b9ad4e4598805e94b6ce
> Reviewed-on: https://chromium-review.googlesource.com/938495
> Reviewed-by: David Tseng <dtseng@chromium.org>
> Commit-Queue: Dominic Mazzoni <dmazzoni@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#540097}

TBR=dmazzoni@chromium.org,dtseng@chromium.org

Change-Id: If3a4f36c64d2a2d2be04d7d520082344edcc1290
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: 808343, 622387
Reviewed-on: https://chromium-review.googlesource.com/944768
Reviewed-by: Karan Bhatia <karandeepb@chromium.org>
Commit-Queue: Karan Bhatia <karandeepb@chromium.org>
Cr-Commit-Position: refs/heads/master@{#540356}
[modify] https://crrev.com/45d0a37bf6cc9b4944aa4710e241c0a81189f2b2/chrome/browser/extensions/api/automation/automation_apitest.cc
[modify] https://crrev.com/45d0a37bf6cc9b4944aa4710e241c0a81189f2b2/chrome/test/data/extensions/api_test/automation/tests/desktop/focus_iframe.js
[modify] https://crrev.com/45d0a37bf6cc9b4944aa4710e241c0a81189f2b2/chrome/test/data/extensions/api_test/automation/tests/desktop/hit_test_iframe.js