[push-api] Push API should recommend implementing ServiceWorkerRegistration.showNotification (#118)

Web developers using the Push API, and subscribing from a document context, will typically check `!!window.Notification` to see whether the Notifications API is implemented, since they cannot easily check from a document context whether the [Notifications Service Worker API][1] (especially `ServiceWorkerRegistration.showNotification` and `ServiceWorkerGlobalScope.onnotificationclick`) is implemented.

Thus the spec should recommend that UAs which implement the Push API either:
a) do not implement the Notifications API at all; or
b) implement and ship [Notifications Service Worker API][1] before or together with shipping the Push API.

[1]: https://notifications.spec.whatwg.org/#service-worker-api

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Reply to this email directly or view it on GitHub:
https://github.com/w3c/push-api/issues/118