validateOriginAndMethodExist(allowedMethods, allowedOrigins) {
        if (allowedOrigins && allowedMethods &&
        Array.isArray(allowedOrigins) &&
        Array.isArray(allowedMethods) &&
        allowedOrigins.length > 0 &&
        allowedMethods.length > 0) {
            return true;
        }
        return errorInstances.MalformedXML
            .customizeDescription(customizedErrs.originAndMethodExist);
    }
_validator.validateOriginAndMethodExist
@param {string[]} allowedMethods - array of AllowedMethod's
@param {string[]} allowedOrigins - array of AllowedOrigin's
@return {(Error|true)} - Arsenal error on failure, true on success