type String - Possible values include service-worker.
serviceWorkerServiceWorkerMainReadonly - The service worker that sent this message
versionId Number - The service worker version ID.
session Session - The Session instance with which the event is associated.
returnValue any - Set this to the value to be returned in a synchronous message
portsMessagePortMain[] - A list of MessagePorts that were transferred with this message
reply Function - A function that will send an IPC message to the renderer frame that sent the original message that you are currently handling. 返信が正しいプロセスとフレームに行くことを保証するために、送信されたメッセージに "返信" する際はこのメソッドを使うべきです。