AdapterView on item selected listener

[dovahkiin98]

This will make settings selection listener easier, and it's still safe for onNothingSelected

fun AdapterView<*>.setOnItemSelectedListener(listener: (view: View?, position: Int, id: Long) -> Unit) {
        onItemSelectedListener = object : AdapterView.OnItemSelectedListener {
            override fun onItemSelected(parent: AdapterView<*>, view: View?, position: Int, id: Long) =
                listener(view, position, id)

            override fun onNothingSelected(parent: AdapterView<*>) = listener(null, -1, 0)
        }
    }

[JakeWharton]

Dupe of #470