[WiX] Wrong handling of the "-culture" property

if (product.type.contains("msi")) {
    var cultures = ModUtils.moduleProperty(product, "cultures");
    args.push("-cultures:" + (cultures ? cultures.join(";") : "null"));
}

if (product.type.contains("msi")) {
    var cultures = ModUtils.moduleProperty(product, "cultures");
    args.push("-cultures:" + (cultures.isEmpty ? cultures.join(";") : "null"));
}