function createStream() {
  const encoder = new goog.global.TextEncoder();
  return new goog.global.ReadableStream({
    start: controller => {
      for (const obj of ['test\r\n', 'test\r\n']) {
        controller.enqueue(encoder.encode(obj));
      }
      controller.close();
    }
  });
}
Creates ReadableStream to upload
@return {!ReadableStream} ReadableStream to upload