The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/8dce930293c30183c265698517e0029d748a5aa3

commit 8dce930293c30183c265698517e0029d748a5aa3
Author: momohatt <momohatt@google.com>
Date: Wed Aug 01 11:34:47 2018

ServiceWorker: Use TRACE_EVENT_WITH_FLOW for tracing fetch events

TRACE_EVENT is currently used but TRACE_EVENT_WITH_FLOW makes it easier to
track the flow of fetch events.

Bug:  860394 
Change-Id: I7aa669ee3769763c31f6b8621bbb1bb466c17ae0
Reviewed-on: https://chromium-review.googlesource.com/1156334
Reviewed-by: Makoto Shimazu <shimazu@chromium.org>
Reviewed-by: Kinuko Yasuda <kinuko@chromium.org>
Commit-Queue: Momoko Hattori <momohatt@google.com>
Cr-Commit-Position: refs/heads/master@{#579761}
[modify] https://crrev.com/8dce930293c30183c265698517e0029d748a5aa3/content/renderer/service_worker/service_worker_context_client.cc

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/ce0a584be6e2db759ab4015a34e96d3d2e382de7

commit ce0a584be6e2db759ab4015a34e96d3d2e382de7
Author: momohatt <momohatt@google.com>
Date: Thu Aug 02 12:01:18 2018

Use TRACE_EVENT_WITH_FLOW for tracing ServiceWorkerContextClient events

This patch makes it easier to track the events dispatched by ServiceWorkerContextClient,
similarly as https://chromium-review.googlesource.com/1156334 .

Events modified in this patch are as follows (in the order of appearance):
* ActivateEvent
* BackgroundFetchAbortEvent
* BackgroundFetchClickEvent
* BackgroundFetchFailEvent
* BackgroundFetchedEvent
* DispatchCookieChangeEvent
* ExtendableMessageEvent
* InstallEvent
* NotificationClickEvent
* NotificationCloseEvent
* PushEvent
* SyncEvent
* AbortPaymentEvent
* CanMakePaymentEvent
* PaymentRequestEvent
* OnNavigationPreload

Bug:  860394 
Change-Id: Ief11e8a755256ccba5c066d94f3481bd52ed2bcb
Reviewed-on: https://chromium-review.googlesource.com/1159939
Reviewed-by: Makoto Shimazu <shimazu@chromium.org>
Commit-Queue: Momoko Hattori <momohatt@google.com>
Cr-Commit-Position: refs/heads/master@{#580135}
[modify] https://crrev.com/ce0a584be6e2db759ab4015a34e96d3d2e382de7/content/renderer/service_worker/service_worker_context_client.cc