get notification data when user click into notification => app opened ( when app killed)

Hi.
I tested with android when app totally closed. I got this function triggered when received notification:

```

messaging().onNotificationOpenedApp(remoteMessage => {
console.log('Notification caused app to open from background state:', remoteMessage)
})

messaging()
.getInitialNotification()
.then(remoteMessage => {
console.log('Notification caused app to open from quit state:', remoteMessage)
})
```

But when user click into notification, app opened without any callback, then i can not get message data. Can someone help?

Start by reproducing the Android case with the app fully killed and a notification click. Inspect the handling around messaging().onNotificationOpenedApp and messaging().getInitialNotification(), then verify that the notification data is available after launch. Done means the callback or initial-notification path exposes the message data when the app opens from a notification.

Written by the indexing model from the issue text.