function NodejsStreamInputAdapter(filename, stream) {
    GenericWorker.call(this, "Nodejs stream input adapter for " + filename);
    this._upstreamEnded = false;
    this._bindStream(stream);
}
A worker that use a nodejs stream as source.
@constructor
@param {String} filename the name of the file entry for this stream.
@param {Readable} stream the nodejs stream.