The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/9aba7a7fea2cddd83a59aef4847ed76cf597e218

commit 9aba7a7fea2cddd83a59aef4847ed76cf597e218
Author: Xida Chen <xidachen@chromium.org>
Date: Thu Aug 16 13:30:59 2018

Disable ProactiveFastShutdownWithUnloadHandler on all platform

TBR=wjmaclean@chromium.org
NOTRY=true

Bug: 874851
Change-Id: I83cc51e272b418a942f324f3e0a408f7b05961d3
Reviewed-on: https://chromium-review.googlesource.com/1177629
Reviewed-by: Xida Chen <xidachen@chromium.org>
Commit-Queue: Xida Chen <xidachen@chromium.org>
Cr-Commit-Position: refs/heads/master@{#583629}
[modify] https://crrev.com/9aba7a7fea2cddd83a59aef4847ed76cf597e218/chrome/browser/resource_coordinator/tab_manager_browsertest.cc

Assigning to fdoray@ as working most actively in tab manager code these days.
-fmeawad@ who has left Chrome.

Note that this is potentially due to a race in Mojo notifications for renderer tear-down and setup, as detailed here:

https://docs.google.com/document/d/1pu-VjoQiPK4w7N04-bMBBKODnqZGb4QHZNuoYgzMU9A/edit#

 Issue 874915  has been merged into this issue.

 Issue 874863  has been merged into this issue.