[ServiceWorker] Remove useless ServiceWorkerVersion::DispatchSimpleEvent().

content/common/service_worker/service_worker_event_dispatcher.mojom

Index: content/common/service_worker/service_worker_event_dispatcher.mojom
diff --git a/content/common/service_worker/service_worker_event_dispatcher.mojom b/content/common/service_worker/service_worker_event_dispatcher.mojom
index 5aa62f8717af990ae2739ed397db40dc051f9149..69d040593170ad32cbd456c8b550a492e3688816 100644
--- a/content/common/service_worker/service_worker_event_dispatcher.mojom
+++ b/content/common/service_worker/service_worker_event_dispatcher.mojom
@@ -54,6 +54,9 @@ struct ExtendableMessageEvent {
 
 // Renderer-side interface bound to ServiceWorkerContextClient for dispatching
 // events.
+// Those events expecting such response
+// (blink.mojom.ServiceWorkerEventStatus, mojo.common.mojom.Time) are dispatched
+// as 'simple event'. See ServiceWorkerVersion for implementation details.

[falken, 2017/03/30 08:21:29]

I would rather phrase this as "... are considered 'simple events'.
ServiceWorkerVersion::CreateSimpleEventCallback can be used to create the
callback for these".

Otherwise it sounds like there is a material difference between how to dispatch
a simple event and non-simple event.

[leonhsl(Using Gerrit), 2017/03/30 09:46:34]

Done.

 interface ServiceWorkerEventDispatcher {
   DispatchActivateEvent()
       => (blink.mojom.ServiceWorkerEventStatus status,