The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/2d193e588955c85b0326043ca3e0feea8c0c0d10

commit 2d193e588955c85b0326043ca3e0feea8c0c0d10
Author: Yutaka Hirano <yhirano@chromium.org>
Date: Tue May 15 05:11:44 2018

[OOR-CORS] Cancel preflight loader synchronously when needed

When the network service is disabled, we are using the same request ID
for the preflight request and the actual request as we cannot assign
separate IDs. We need to tear down the preflight request first, and
then make the actual request: Otherwise we will see a renderer crash
caused by RDH_INVALID_REQUEST_ID.

Currently we cancel the request by resetting the SimpleURLLoader for
the preflight request: That is not enough because destroying a
SimpleURLLoader asynchronously cancels a request, and we don't know
when it's actually destroyed. This is especially problematic when
a server returns a preflight with a long body.

This CL fixes the problem by adding a function which cancels the
request synchronously. This is a workaround, and we won't need the
logic in the end.


Bug: 838136, 614281,  842593 
Cq-Include-Trybots: master.tryserver.chromium.linux:linux_mojo
Change-Id: Ic9d20cfbecc7c5b8749e0dc664d12c6d07e8c673
Reviewed-on: https://chromium-review.googlesource.com/1056941
Commit-Queue: Yutaka Hirano <yhirano@chromium.org>
Reviewed-by: Takashi Toyoshima <toyoshim@chromium.org>
Reviewed-by: Kinuko Yasuda <kinuko@chromium.org>
Cr-Commit-Position: refs/heads/master@{#558617}
[modify] https://crrev.com/2d193e588955c85b0326043ca3e0feea8c0c0d10/content/browser/loader/resource_message_filter.cc
[modify] https://crrev.com/2d193e588955c85b0326043ca3e0feea8c0c0d10/services/network/cors/cors_url_loader.cc
[modify] https://crrev.com/2d193e588955c85b0326043ca3e0feea8c0c0d10/services/network/cors/cors_url_loader.h
[modify] https://crrev.com/2d193e588955c85b0326043ca3e0feea8c0c0d10/services/network/cors/cors_url_loader_factory.cc
[modify] https://crrev.com/2d193e588955c85b0326043ca3e0feea8c0c0d10/services/network/cors/cors_url_loader_factory.h
[modify] https://crrev.com/2d193e588955c85b0326043ca3e0feea8c0c0d10/services/network/cors/preflight_controller.cc
[modify] https://crrev.com/2d193e588955c85b0326043ca3e0feea8c0c0d10/services/network/cors/preflight_controller.h
[modify] https://crrev.com/2d193e588955c85b0326043ca3e0feea8c0c0d10/services/network/cors/preflight_controller_unittest.cc