code: func RemoveMagicPrefixLine(body []byte) []byte {
  	if bytes.HasPrefix(body, magicPrefix) {
  		return body[5:]
  	}
  	return body
  }
docs: // RemoveMagicPrefixLine removes the "magic prefix line" of Gerris JSON
  // response if present. The JSON response body starts with a magic prefix line
  // that must be stripped before feeding the rest of the response body to a JSON
  // parser. The reason for this is to prevent against Cross Site Script
  // Inclusion (XSSI) attacks.  By default all standard Gerrit APIs include this
  // prefix line though some plugins may not.
  //
  // Gerrit API docs: https://gerrit-review.googlesource.com/Documentation/rest-api.html#output