code: function UserRealm(callContext, userPrinciple, authority) {
    this._log = new Logger('UserRealm', callContext._logContext);
    this._callContext = callContext;
    this._apiVersion = '1.0';
    this._federationProtocol = null;
    this._accountType = null;
    this._federationMetadataUrl = null;
    this._federationActiveAuthUrl = null;
    this._userPrinciple = userPrinciple;
    this._authority = authority;
  }
docs: Create a new UserRealm object
  @private
  @constructor
  @param {object} callContext Contains any context information that applies to the request.
  @param {string} userPrinciple   The username for which a realm needs to be discovered.
  @param {string} authority       The string url of the authority that owns the userPrinciple.