notif.opened_from_tray evaluates true when opening app via app icon

**Versions**
react-native-cli: 2.0.1
react-native: 0.42.3
react-native-fcm: 7.5.1
Device: Android Emulator Version 6

**Problem**

Q1. `notif.opened_from_tray` evaluates to true even though no notification has been sent to the device when the application is brought from background to foreground.

This is the contents of the notif object

`{
"opened_from_tray": 1,
"fcm": {
"action": "android.intent.action.MAIN"
},
"profile": 0
}`

Is this a valid result?

Further, calling FCM.getInitialNotification does not return the visible contents that were presented in the notification

Start with the Android handling behind FCM.getInitialNotification and the notif.opened_from_tray value. Reproduce the app-icon foreground transition without a notification, then compare it with a notification launch; done requires the observed flag and initial-notification contents to match the documented behavior.

Written by the indexing model from the issue text.