docs: function _setAuthHeaderFromAuthInfo(headers, authInfo) {
      if (authInfo.token) {
          headers.authorization = 'Bearer ' + authInfo.token;
      } else if (authInfo.username) {
          headers.authorization = _basicAuthHeader(authInfo.username,
              authInfo.password);
      } else if (headers.authorization) {
          delete headers.authorization;
      }
  }