[push-api] Push event shouldn't be dispatched to an activating worker (#147)

The current spec will deliver a push event to the "active worker". However, this worker may have status "activating" rather than "activated". The SW spec intends for "activating" workers to not receive functional events yet (https://slightlyoff.github.io/ServiceWorker/spec/service_worker/index.html#service-worker-state), so Push spec probably should also do the same.

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Reply to this email directly or view it on GitHub:
https://github.com/w3c/push-api/issues/147