The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/3119de7fdc780a76a5bac31f5667f3bb2ef41c92

commit 3119de7fdc780a76a5bac31f5667f3bb2ef41c92
Author: Kenichi Ishibashi <bashi@chromium.org>
Date: Fri Jan 11 03:34:52 2019

Update comment in ServiceWorkerGlobalScopeClient::From()

The bug referenced in the function was closed as WontFix but
we still see crashes. Update the comment so that we don't change
CHECK() to DCHECK() until crashes are gone.

Bug: 920854
Change-Id: Id07a2f69870531f2d8ddd78fa55963950d603e74
Reviewed-on: https://chromium-review.googlesource.com/c/1405152
Reviewed-by: Kenichi Ishibashi <bashi@chromium.org>
Reviewed-by: Tsuyoshi Horo <horo@chromium.org>
Commit-Queue: Kenichi Ishibashi <bashi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#621889}
[modify] https://crrev.com/3119de7fdc780a76a5bac31f5667f3bb2ef41c92/third_party/blink/renderer/modules/service_worker/service_worker_global_scope_client.cc