writeChunk method
Implementation
@override
Future<void> writeChunk(String session, Uint8List data) async {
// Direct JNI call -- this is what used to be one `invokeMethod` per
// chunk. For a multi-MB file written in, say, 64KB chunks that's
// hundreds of MethodChannel round trips avoided.
SafStreamJniIo.writeChunk(session, data);
}