The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/bbe91c3fce98e333afcfee27f38fee111260ded4

commit bbe91c3fce98e333afcfee27f38fee111260ded4
Author: Guido Urdaneta <guidou@chromium.org>
Date: Tue Feb 06 16:26:45 2018

Disable flaky GenericSensorBrowserTest.AmbientLightSensorTest on Windows

Bug:  809537 
Change-Id: I54951259e0b64944c92c0d28e06f16e4584b7460
TBR: reillyg@chromium.org
Reviewed-on: https://chromium-review.googlesource.com/904643
Reviewed-by: Guido Urdaneta <guidou@chromium.org>
Cr-Commit-Position: refs/heads/master@{#534694}
[modify] https://crrev.com/bbe91c3fce98e333afcfee27f38fee111260ded4/content/browser/generic_sensor_browsertest.cc

Mikhail, can you take a look?

The assigned owner "mikhail.pozdnyakov@intel.com" is not able to receive e-mails, please re-triage.

For more details visit https://www.chromium.org/issue-tracking/autotriage - Your friendly Sheriffbot

I think that this is fixed but need to double-check. Since this test has been disabled there is no current data in the flakiness dashboard.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/aa03d3a04070f6a5549ac47e43c189c994b4ea63

commit aa03d3a04070f6a5549ac47e43c189c994b4ea63
Author: Reilly Grant <reillyg@chromium.org>
Date: Mon Jun 18 21:32:28 2018

Read initial sensor reading from shared memory on initialization

A sensor's initial reading is checked to see if an event should be
fired immediately after it is activated. Unfortunately this initial
reading was not actually read from shared memory. Depending on timing
the reading might be refreshed by the polling timer or upon receiving
a SensorReadingChanged message.

This patch updates the code to take this initial reading on
initialization so that we can reliably decide whether to send an
initial reading event.

Bug:  789515 , 809537 
Change-Id: I96f441aad3ec474ef94fd634aa34bf9b29b9edf9
Reviewed-on: https://chromium-review.googlesource.com/1103178
Reviewed-by: Jun Cai <juncai@chromium.org>
Commit-Queue: Reilly Grant <reillyg@chromium.org>
Cr-Commit-Position: refs/heads/master@{#568169}
[modify] https://crrev.com/aa03d3a04070f6a5549ac47e43c189c994b4ea63/content/browser/generic_sensor/generic_sensor_browsertest.cc
[modify] https://crrev.com/aa03d3a04070f6a5549ac47e43c189c994b4ea63/content/test/data/generic_sensor/ambient_light_sensor_test.html
[modify] https://crrev.com/aa03d3a04070f6a5549ac47e43c189c994b4ea63/third_party/blink/renderer/modules/sensor/sensor_proxy_impl.cc

I believe this flakiness has been fixed. Setting next action for 2 days from now to double-check on the flakiness dashboard:

https://test-results.appspot.com/dashboards/flakiness_dashboard.html#testType=content_browsertests&tests=GenericSensorBrowserTest.AmbientLightSensorTest

The NextAction date has arrived: 2018-06-20

Verified no more flakiness appearing on the dashboard.