HtmlFromXamlConverter.cs doesn't set units on CSS font-size attribute

For all I know setting the units on a CSS font-size attribute is mandatory. I updated line 162 to the following in order to make it specify the font-size in points:

css = "font-size:" 
    + Math.Round(double.Parse(xamlReader.Value, CultureInfo.InvariantCulture) / (96.0 / 72.0), 2)
      .ToString("0.##", CultureInfo.InvariantCulture) + "pt;";

This only works for when the FontSize in the XAML is specified in points and without units (as it's generated by XamlWriter.Save).