[PR] Add type definitions for service worker PushManager
[PR] Add type definitions for service worker PushManager

Summary:
Library definitions for service worker `PushManager` and some fixes in `ServiceWorkerRegistration` and `ServiceWorkerContainer` definitions.

https://w3c.github.io/push-api
https://w3c.github.io/ServiceWorker
Pull Request resolved: https://github.com/facebook/flow/pull/7478

Reviewed By: nmote

Differential Revision: D14406504

Pulled By: dsainati1

fbshipit-source-id: f3c40e4a33dadf3f0174526dc7905b1afb7a74e9

gabelevi/flow,facebook/flow,gabelevi/flow,samwgoldman/flow,samwgoldman/flow,samwgoldman/flow,facebook/flow,mroch/flow,mroch/flow,gabelevi/flow,facebook/flow,facebook/flow,gabelevi/flow,gabelevi/flow,mroch/flow,gabelevi/flow,gabelevi/flow,mroch/flow,facebook/flow,mroch/flow,samwgoldman/flow,samwgoldman/flow,mroch/flow,samwgoldman/flow,mroch/flow,facebook/flow,facebook/flow,samwgoldman/flow