Calling "sendFollowerNotification" from Android

Regrettably, Google Groups says that they are NOT for questions about code, and I received absolutely no help from Stackoverflow. I've read all of the docs and scoured the internet, but I have not found a single answer... or even the question:

How would you call the "sendFollowerNotification" function from an Android app?

There is LITERALLY nowhere else on the face of the Earth I can ask this question... unfortunately. And I have thoroughly exhausted myself for the better part of two months looking.

I've reached a point where my app automatically adds users and notification tokens to the realtime database... but I still have no idea how to trigger the function that will ultimately send those users a follower notification.

I'm aware that you can call functions like this:

```java
FirebaseFunctions.getInstance()
.getHttpsCallable("myCoolFunction")
.call(optionalObject)
.addOnFailureListener {
Log.wtf("FF", it)
}
.addOnSuccessListener {

}
```

...but I'm unsure of what variable to send to something like sendFollowerNotification... or how to send it. If you could explain it here that would already be great... and even better if you added that information to the official README.