code: public void setFillOutlineColor(@ColorInt int color) {
      jsonObject.addProperty(FillOptions.PROPERTY_FILL_OUTLINE_COLOR, ColorUtils.colorToRgbaString(color));
    }
docs: Set the FillOutlineColor property
  <p>
  The outline color of the fill. Matches the value of {@link PropertyFactory#fillColor} if unspecified.
  </p>
  <p>
  To update the fill on the map use {@link FillManager#update(Annotation)}.
  <p>
  
  @param color value for String