function newReadableStream(underlyingSource) {
  /** @const {!ReadableStreamSource} */
  const source = {
    start(controller) {
      return underlyingSource.start(
          new NativeReadableStreamDefaultController(controller));
    },
  };
  const stream = new ReadableStream(source);
  return new NativeReadableStream(stream);
}
@param {!liteTypes.ReadableStreamUnderlyingSource<T>} underlyingSource
@return {!NativeReadableStream<T>}
@suppress {strictMissingProperties}
@template T