The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/dfe8581266c0c626071fd74334d82526f1536601

commit dfe8581266c0c626071fd74334d82526f1536601
Author: Xida Chen <xidachen@chromium.org>
Date: Wed Aug 15 17:11:21 2018

Disable BackgroundRenderersAreThrottled on all platform

Flakiness dashboard shows that it has been flaky for a while

TBR=wjmaclean@chromium.org
NOTRY=true

Bug:  874497 
Change-Id: I017096a3a33ba69cab80cf9f78caa59bd4672319
Reviewed-on: https://chromium-review.googlesource.com/1175939
Reviewed-by: Xida Chen <xidachen@chromium.org>
Commit-Queue: Xida Chen <xidachen@chromium.org>
Cr-Commit-Position: refs/heads/master@{#583289}
[modify] https://crrev.com/dfe8581266c0c626071fd74334d82526f1536601/third_party/blink/renderer/core/scheduler/throttling_test.cc

 Issue 873778  has been merged into this issue.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/083ceb97876d2773366b82da34ce013f7d78f136

commit 083ceb97876d2773366b82da34ce013f7d78f136
Author: Alexander Timin <altimin@chromium.org>
Date: Mon Aug 20 14:06:07 2018

[scheduler] Deflake BackgroundRenderersAreThrottled test.

R=skyostil@chromium.org
BUG= 874497 

Change-Id: Ia5546b2600b2502e3a5fa00c6631810af377d0de
Reviewed-on: https://chromium-review.googlesource.com/1181027
Reviewed-by: Sami Kyöstilä <skyostil@chromium.org>
Commit-Queue: Alexander Timin <altimin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#584431}
[modify] https://crrev.com/083ceb97876d2773366b82da34ce013f7d78f136/third_party/blink/renderer/core/scheduler/throttling_test.cc

This should be fixed now. Will check next Monday and will close the bug if it's the case.

The NextAction date has arrived: 2018-08-26

Seems good now.