util.CheckErr(err)

with

if err != nil {
	return err
}

One replacement is incorrent. The current call of resource.NewBuilder is returned in r variable. Which was tested with util.CheckErr(r.Err()) before cd7d78b6 commit. It was replaced by

if err != nil {
	return err
}

which is incorrect as err is not set by resource.NewBuilder call. The correct use is

err := r.Err()
if err != nil {
	return err
}