The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/322875f4d93696a3d789151e5a385cafbdcf9f69

commit 322875f4d93696a3d789151e5a385cafbdcf9f69
Author: skyostil <skyostil@chromium.org>
Date: Fri Jun 03 10:13:14 2016

headless: Migrate to URLRequestContextBuilder

Migrate to using URLRequestContextBuilder, which lets us remove a lot of
redundant network setup code.

BUG= 616475 

Review-Url: https://codereview.chromium.org/2033773002
Cr-Commit-Position: refs/heads/master@{#397673}

[modify] https://crrev.com/322875f4d93696a3d789151e5a385cafbdcf9f69/headless/lib/browser/headless_browser_context.cc
[modify] https://crrev.com/322875f4d93696a3d789151e5a385cafbdcf9f69/headless/lib/browser/headless_url_request_context_getter.cc
[modify] https://crrev.com/322875f4d93696a3d789151e5a385cafbdcf9f69/headless/lib/browser/headless_url_request_context_getter.h