Describes the event being added.
Callback passes an object with the cards as of the latest refresh.
Callback passes an object with the banners as of the latest refresh.
Callback passes an object containing "error_code", "user_id", "original_signature", and "reason".
Callback passes the BrazeInAppMessage object.
Callback passes the Feature Flags array.
Only supported on Android.
Notifies the bridge of a listener being added.