The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/8efa11f6f6967938e6b84fe4b800cb1d898dff6d

commit 8efa11f6f6967938e6b84fe4b800cb1d898dff6d
Author: John Abd-El-Malek <jam@chromium.org>
Date: Sun Jan 06 00:51:53 2019

Support registerProtocolHandler with network service.

Bug:  919246 
Change-Id: I99692b434fac2b3e70b07cd1b9e183660cd34aff
Reviewed-on: https://chromium-review.googlesource.com/c/1396156
Reviewed-by: Doug Turner <dougt@chromium.org>
Commit-Queue: John Abd-El-Malek <jam@chromium.org>
Cr-Commit-Position: refs/heads/master@{#620201}
[modify] https://crrev.com/8efa11f6f6967938e6b84fe4b800cb1d898dff6d/chrome/browser/chrome_content_browser_client.cc
[modify] https://crrev.com/8efa11f6f6967938e6b84fe4b800cb1d898dff6d/chrome/browser/custom_handlers/protocol_handler_registry.cc
[modify] https://crrev.com/8efa11f6f6967938e6b84fe4b800cb1d898dff6d/chrome/browser/custom_handlers/protocol_handler_registry.h
[modify] https://crrev.com/8efa11f6f6967938e6b84fe4b800cb1d898dff6d/chrome/browser/custom_handlers/protocol_handler_registry_browsertest.cc
[modify] https://crrev.com/8efa11f6f6967938e6b84fe4b800cb1d898dff6d/chrome/browser/predictors/loading_data_collector.cc
[modify] https://crrev.com/8efa11f6f6967938e6b84fe4b800cb1d898dff6d/chrome/browser/profiles/profile_io_data.cc
[modify] https://crrev.com/8efa11f6f6967938e6b84fe4b800cb1d898dff6d/chrome/browser/profiles/profile_io_data.h
[modify] https://crrev.com/8efa11f6f6967938e6b84fe4b800cb1d898dff6d/content/browser/loader/navigation_url_loader_impl.cc
[modify] https://crrev.com/8efa11f6f6967938e6b84fe4b800cb1d898dff6d/content/common/throttling_url_loader.cc
[modify] https://crrev.com/8efa11f6f6967938e6b84fe4b800cb1d898dff6d/testing/buildbot/filters/mojo.fyi.network_browser_tests.filter

This bug requires manual review: M72 has already been promoted to the beta branch, so this requires manual review
Please contact the milestone owner if you have questions.
Owners: govind@(Android), kariahda@(iOS), djmm@(ChromeOS), abdulsyed@(Desktop)

For more details visit https://www.chromium.org/issue-tracking/autotriage - Your friendly Sheriffbot

How is the change looking in canary? Is it safe to merge now?

It's been on 2 canaries so far (3663 & 3664) and I don't see any crashes. This should be safe to merge as the actual change is a small number of lines, and it's only in the network service path which is turned on via Finch.

Approving merge to M72 branch 3626 based on comment #6. Please merge ASAP. Thank you.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/f0b70fbee6bf692b79e8f0e512704ff9f92ff754

commit f0b70fbee6bf692b79e8f0e512704ff9f92ff754
Author: John Abd-El-Malek <jam@chromium.org>
Date: Mon Jan 07 18:47:50 2019

Support registerProtocolHandler with network service.

TBR=jam@chromium.org

refs/heads/master@{#620201} (cherry picked from commit 8efa11f6f6967938e6b84fe4b800cb1d898dff6d)

Bug:  919246  Change-Id: I99692b434fac2b3e70b07cd1b9e183660cd34aff Reviewed-on: https://chromium-review.googlesource.com/c/1396156
Change-Id: I8076bc315e1733b7a694d61cbfc36faa2ea92f37
Reviewed-by: Doug Turner <dougt@chromium.org> Commit-Queue: John Abd-El-Malek <jam@chromium.org> Cr-Commit-Position:
Reviewed-on: https://chromium-review.googlesource.com/c/1398386
Reviewed-by: John Abd-El-Malek <jam@chromium.org>
Cr-Commit-Position: refs/branch-heads/3626@{#595}
Cr-Branched-From: d897fb137fbaaa9355c0c93124cc048824eb1e65-refs/heads/master@{#612437}
[modify] https://crrev.com/f0b70fbee6bf692b79e8f0e512704ff9f92ff754/chrome/browser/chrome_content_browser_client.cc
[modify] https://crrev.com/f0b70fbee6bf692b79e8f0e512704ff9f92ff754/chrome/browser/custom_handlers/protocol_handler_registry.cc
[modify] https://crrev.com/f0b70fbee6bf692b79e8f0e512704ff9f92ff754/chrome/browser/custom_handlers/protocol_handler_registry.h
[modify] https://crrev.com/f0b70fbee6bf692b79e8f0e512704ff9f92ff754/chrome/browser/custom_handlers/protocol_handler_registry_browsertest.cc
[modify] https://crrev.com/f0b70fbee6bf692b79e8f0e512704ff9f92ff754/chrome/browser/predictors/loading_data_collector.cc
[modify] https://crrev.com/f0b70fbee6bf692b79e8f0e512704ff9f92ff754/chrome/browser/profiles/profile_io_data.cc
[modify] https://crrev.com/f0b70fbee6bf692b79e8f0e512704ff9f92ff754/chrome/browser/profiles/profile_io_data.h
[modify] https://crrev.com/f0b70fbee6bf692b79e8f0e512704ff9f92ff754/content/browser/loader/navigation_url_loader_impl.cc
[modify] https://crrev.com/f0b70fbee6bf692b79e8f0e512704ff9f92ff754/content/common/throttling_url_loader.cc
[modify] https://crrev.com/f0b70fbee6bf692b79e8f0e512704ff9f92ff754/testing/buildbot/filters/mojo.fyi.network_browser_tests.filter