The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/36ffbe7850c1b2495d4ba62ae1d3872f4788db8e

commit 36ffbe7850c1b2495d4ba62ae1d3872f4788db8e
Author: Ovidio Henriquez <odejesush@chromium.org>
Date: Fri May 18 20:56:35 2018

Allow WebUSB to work in a Dedicated Worker

This change updates the USB class to allow the exposed APIs to work
correctly in the context of a Dedicated Worker. In order to do this, USB
was reworked to use an ExecutionContext object to check the context and
the FeaturePolicy, rather than the LocalFrame that it was using
previously. The usb layout test for workers was also updated to use the
WebUSB test API to check that getDevices and event listeners work in
Dedicated Workers.

Additionally, the UsbDeviceManager Mojo interface used by WebUSB is
added to the DedicatedWorkerHost BinderRegistry so that the request is
handled correctly.

Bug:  837414 , 837422 
Change-Id: I1ad95e288312851e9ec39ce6ec917bf38b12d4d6
Reviewed-on: https://chromium-review.googlesource.com/1045309
Commit-Queue: Ovidio Henriquez <odejesush@chromium.org>
Reviewed-by: Greg Kerr <kerrnel@chromium.org>
Reviewed-by: Hiroki Nakagawa <nhiroki@chromium.org>
Reviewed-by: Reilly Grant <reillyg@chromium.org>
Reviewed-by: Chong Zhang <chongz@chromium.org>
Cr-Commit-Position: refs/heads/master@{#560026}
[modify] https://crrev.com/36ffbe7850c1b2495d4ba62ae1d3872f4788db8e/content/browser/dedicated_worker/dedicated_worker_host.cc
[modify] https://crrev.com/36ffbe7850c1b2495d4ba62ae1d3872f4788db8e/content/public/app/mojo/content_browser_manifest.json
[modify] https://crrev.com/36ffbe7850c1b2495d4ba62ae1d3872f4788db8e/third_party/WebKit/LayoutTests/external/wpt/resources/chromium/webusb-test.js
[modify] https://crrev.com/36ffbe7850c1b2495d4ba62ae1d3872f4788db8e/third_party/WebKit/LayoutTests/external/wpt/webusb/resources/usb-helpers.js
[modify] https://crrev.com/36ffbe7850c1b2495d4ba62ae1d3872f4788db8e/third_party/WebKit/LayoutTests/external/wpt/webusb/resources/usb.dedicatedworker.sharedworker.js
[modify] https://crrev.com/36ffbe7850c1b2495d4ba62ae1d3872f4788db8e/third_party/WebKit/LayoutTests/webexposed/global-interface-listing-dedicated-worker-expected.txt
[modify] https://crrev.com/36ffbe7850c1b2495d4ba62ae1d3872f4788db8e/third_party/WebKit/LayoutTests/webexposed/global-interface-listing-shared-worker-expected.txt
[modify] https://crrev.com/36ffbe7850c1b2495d4ba62ae1d3872f4788db8e/third_party/blink/renderer/modules/webusb/usb.cc
[modify] https://crrev.com/36ffbe7850c1b2495d4ba62ae1d3872f4788db8e/third_party/blink/renderer/modules/webusb/usb.h
[modify] https://crrev.com/36ffbe7850c1b2495d4ba62ae1d3872f4788db8e/third_party/blink/renderer/modules/webusb/usb_connection_event.idl