Returns the standard On Appearance for a CheckBox

@returns {AcroFormXObject}
function YesPushDown(formObject) {
        var xobj = createFormXObject(formObject);
        var stream = [];
        var fontKey = scope.internal.getFont(formObject.fontName, formObject.fontStyle).id;

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

        var calcRes = calculateX(formObject, formObject.caption);
        stream.push("0.749023 g");
        stream.push("0 0 " + f2(AcroFormAppearance.internal.getWidth(formObject)) + " " + f2(AcroFormAppearance.internal.getHeight(formObject)) + " re");
        stream.push("f");
        stream.push("BMC");
        stream.push("q");
        stream.push("0 0 1 rg");
        stream.push("/" + fontKey + " " + f2(calcRes.fontSize) + " Tf " + encodedColor);
        stream.push("BT");
        stream.push(calcRes.text);
        stream.push("ET");
        stream.push("Q");
        stream.push("EMC");
        xobj.stream = stream.join("\n");
        return xobj;
      }