.getToken() method on AngularFireMessaging fails too early on notification mermission.

[nmggithub]

Version info

Angular: 11.2.0

Firebase: 8.2.7

AngularFire: 6.1.4

How to reproduce these conditions

Steps to set up and reproduce
Simply call .getToken() on an AngularFireMessaging object when the notification permission in the browser is set to default.

Debug output

None / N/A

Expected behavior

As is the case with the regular firebase.messaging() object, it requests the permission when called.

Actual behavior

The notification permission is not requested, and the observable returns null.

[geromegrignon]

Do you use Angular Service Worker? https://github.com/angular/angularfire/blob/master/docs/messaging/messaging.md

[nmggithub]

Do you use Angular Service Worker? https://github.com/angular/angularfire/blob/master/docs/messaging/messaging.md

No I do not. This issue is only here because the PR I made required one. This is a failure in the code logic.

[jamesdaniels]

the new v7 api, modular, mirrors the JS SDK exactly rather than keeping with legacy