int getPriorityByImportance() {
        switch(getAndroidChannelImportance()){
            case NotificationManagerCompat.IMPORTANCE_NONE: // 0
            case NotificationManagerCompat.IMPORTANCE_MIN: // 1
                return NotificationCompat.PRIORITY_MIN;

            case NotificationManagerCompat.IMPORTANCE_LOW: // 2
                return NotificationCompat.PRIORITY_LOW;

            case NotificationManagerCompat.IMPORTANCE_DEFAULT: // 3
                return NotificationCompat.PRIORITY_DEFAULT;

            case NotificationManagerCompat.IMPORTANCE_HIGH: // 4
            case NotificationManagerCompat.IMPORTANCE_MAX: // 5
                return NotificationCompat.PRIORITY_MAX;
        }

        return NotificationCompat.PRIORITY_DEFAULT;
    }
For Android 7 backward compatibility. Gets the notifications priority
based on {@link #getAndroidChannelImportance()}
src/android/Options.java