The test was flaky in https://ci.chromium.org/p/chromium/builders/luci.chromium.try/linux_chromium_asan_rel_ng

When the test failed it failed with the following error:

[22719:22719:0730/155622.337277:FATAL:site_per_process_hit_test_browsertest.cc(4876)] Check failed: hit_test_data.size() >= 3
....


It recently failed in build

https://ci.chromium.org/p/chromium/builders/luci.chromium.try/linux_chromium_tsan_rel_ng/69704

https://ci.chromium.org/p/chromium/builders/luci.chromium.try/linux_chromium_asan_rel_ng/66583

...

As Sheriff I'm trying to find a good owner for this. Assigning the bug to sunxd@ who added the test code not too long ago.

Could you please take a look or re-route the bug? Thanks a lot

Thanks, I'm going to take a look at it.

 Issue 868640  has been merged into this issue.

One out of three runs the hit test region observer gets a smaller hit test region list than anticipated.

I guess the test is flaky because the subframe is not completely loaded sometimes. I think a fix is to wait until the observer has been supplied with expected number of hit test regions?

 Issue 871648  has been merged into this issue.

 Issue 872763  has been merged into this issue.

 Issue 872761  has been merged into this issue.

A variety of tests are flaky as a result of https://chromium-review.googlesource.com/c/chromium/src/+/1000135 ; see https://findit-for-me.appspot.com/waterfall/flake/flake-culprit?key=ag9zfmZpbmRpdC1mb3ItbWVyQwsSDEZsYWtlQ3VscHJpdCIxY2hyb21pdW0vNWYzNDU5ZWI2OTE5ZDNlYzgzYjI4NDgxMzIwZGYwNGRiZGUwZmY1NAw .

Please revert the CL or mark all affected tests flaky and determine the root cause.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/ae52aa4fe615d1eb071b47542294732f4b344daa

commit ae52aa4fe615d1eb071b47542294732f4b344daa
Author: sunxd <sunxd@chromium.org>
Date: Fri Aug 10 18:21:59 2018

Fix flaky SitePerProcessHitTestDataGenerationTest

This patch attempts to fix the flaky content browsertest. The suspected
reason of the test being flaky is that the subframe content is not fully
loaded and processed when hit test data is collected. This patch force
the test to wait until all subframes receive their hit test query entries,
and retrieve hit test data directly from root frame hit test query.

Bug:  869314 
Cq-Include-Trybots: luci.chromium.try:android_optional_gpu_tests_rel
Change-Id: Iccace2dfd11b613cccf67a23cf5fc8552f31544d
Reviewed-on: https://chromium-review.googlesource.com/1161972
Reviewed-by: Jonathan Ross <jonross@chromium.org>
Reviewed-by: Antoine Labour <piman@chromium.org>
Reviewed-by: Robert Flack <flackr@chromium.org>
Commit-Queue: Xianda Sun <sunxd@chromium.org>
Cr-Commit-Position: refs/heads/master@{#582253}
[modify] https://crrev.com/ae52aa4fe615d1eb071b47542294732f4b344daa/components/viz/host/hit_test/hit_test_query.h
[modify] https://crrev.com/ae52aa4fe615d1eb071b47542294732f4b344daa/content/browser/site_per_process_hit_test_browsertest.cc
[modify] https://crrev.com/ae52aa4fe615d1eb071b47542294732f4b344daa/content/public/test/hit_test_region_observer.cc
[modify] https://crrev.com/ae52aa4fe615d1eb071b47542294732f4b344daa/content/public/test/hit_test_region_observer.h

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/8ed2701c54c58ef5afa63047364a7fcee91b6049

commit 8ed2701c54c58ef5afa63047364a7fcee91b6049
Author: sunxd <sunxd@chromium.org>
Date: Mon Aug 13 20:47:53 2018

Enable SitePerProcessHitTestDataGenerationBrowserTest

The test was previously disabled due to being flaky. Now that the fixing
patch was landed, we should enable this test again.

Bug:  869314 
Change-Id: I7faf6103cd1d5232d058494fe3c4e3018fe96db6
Reviewed-on: https://chromium-review.googlesource.com/1173267
Reviewed-by: Ken Buchanan <kenrb@chromium.org>
Commit-Queue: Xianda Sun <sunxd@chromium.org>
Cr-Commit-Position: refs/heads/master@{#582695}
[modify] https://crrev.com/8ed2701c54c58ef5afa63047364a7fcee91b6049/content/browser/site_per_process_hit_test_browsertest.cc