message: Write test using binary, otherwise \n will become \r\n leading to double \r\r\n.
diff: @@ -450,7 +450,8 @@ void UpdateTestExpectation(const std::string& filename,
  str.replace(it, expectation.size(), actual);
  // Write it back out.
  - std::ofstream of(filename, std::ios::out | std::ios::trunc);
  + std::ofstream of(filename,
  + std::ios::out | std::ios::trunc | std::ios::binary);
  of.write(str.c_str(), str.size());
  of.close();
  }
  