I'd like to work on it.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/c910116b059dcc885c40271a7a845ffd90d16a21

commit c910116b059dcc885c40271a7a845ffd90d16a21
Author: Amos Lim <eui-sang.lim@samsung.com>
Date: Mon May 28 10:22:27 2018

Remove redundant request ids passed when dispatching PaymentRequest events

ServiceWorkerEventDispatcher methods for dispatching events take
|event_id| or |payment_request_id| but it's not used.

Bug:  802974 
Change-Id: Ie79e17716d5c6916b8df125e17a886da2abac0d0
Reviewed-on: https://chromium-review.googlesource.com/1071315
Reviewed-by: Makoto Shimazu <shimazu@chromium.org>
Reviewed-by: Kinuko Yasuda <kinuko@chromium.org>
Commit-Queue: Kinuko Yasuda <kinuko@chromium.org>
Cr-Commit-Position: refs/heads/master@{#562226}
[modify] https://crrev.com/c910116b059dcc885c40271a7a845ffd90d16a21/content/browser/payments/payment_app_provider_impl.cc
[modify] https://crrev.com/c910116b059dcc885c40271a7a845ffd90d16a21/content/browser/service_worker/embedded_worker_test_helper.cc
[modify] https://crrev.com/c910116b059dcc885c40271a7a845ffd90d16a21/content/common/service_worker/service_worker_event_dispatcher.mojom
[modify] https://crrev.com/c910116b059dcc885c40271a7a845ffd90d16a21/content/renderer/service_worker/service_worker_context_client.cc
[modify] https://crrev.com/c910116b059dcc885c40271a7a845ffd90d16a21/content/renderer/service_worker/service_worker_context_client.h