The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/f58ae1e7e8f49db70eb92d16b2cef1b420f4edff

commit f58ae1e7e8f49db70eb92d16b2cef1b420f4edff
Author: Roger McFarlane <rogerm@chromium.org>
Date: Fri Aug 17 15:27:58 2018

[autofill] Control autofill server communciation via Finch

This CL adds a feature flag to enable/disable communication with the
autofill server. It further adds a feature parameter by which the
autofill server URL can be controlled.

This functionality is to support:

  - routing a % of users to exercise a staging server environment
    to ensure better server validation before rollout.

  - turning off or rerouting autofill server traffic from the test
    bots.

By default, autofill server communication is enabled and will send
traffic to the existing autofill server.

Bug: 874553,  866940 
Change-Id: I8a425c76d483731fce9ef0ef8e10ac0cc145cb1d
Reviewed-on: https://chromium-review.googlesource.com/1176287
Commit-Queue: Roger McFarlane <rogerm@chromium.org>
Reviewed-by: Moe Ahmadi <mahmadi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#584076}
[modify] https://crrev.com/f58ae1e7e8f49db70eb92d16b2cef1b420f4edff/components/autofill/core/browser/autofill_download_manager.cc
[modify] https://crrev.com/f58ae1e7e8f49db70eb92d16b2cef1b420f4edff/components/autofill/core/browser/autofill_download_manager.h
[modify] https://crrev.com/f58ae1e7e8f49db70eb92d16b2cef1b420f4edff/components/autofill/core/browser/autofill_download_manager_unittest.cc
[modify] https://crrev.com/f58ae1e7e8f49db70eb92d16b2cef1b420f4edff/components/autofill/core/common/autofill_features.cc
[modify] https://crrev.com/f58ae1e7e8f49db70eb92d16b2cef1b420f4edff/components/autofill/core/common/autofill_features.h