Returns the standard Appearance

@returns {AcroFormXObject}
function createDefaultAppearanceStream(formObject) {
      // Set Helvetica to Standard Font (size: auto)
      // Color: Black
      var fontKey = scope.internal.getFont(formObject.fontName, formObject.fontStyle).id;

      var encodedColor = scope.__private__.encodeColorString(formObject.color);

      var fontSize = formObject.fontSize;
      var result = '/' + fontKey + ' ' + fontSize + ' Tf ' + encodedColor;
      return result;
    }