code: function formatClassType(data, type) {
      if (typeof(data) === 'undefined') {
        return undefined;
      }
  
      if (data instanceof type) {
        return data;
      }
      return new type(data);
    }
docs: Creates or returns a class instance of a given type with the initialization
  data if the data is not already an instance of the given type.
  
  @example
  var time = new ICAL.Time(...);
  var result = ICAL.helpers.formatClassType(time, ICAL.Time);
  
  (result instanceof ICAL.Time)
  // => true
  
  result = ICAL.helpers.formatClassType({}, ICAL.Time);
  (result isntanceof ICAL.Time)
  // => true
  
  
  @param {Object} data       object initialization data
  @param {Object} type       object type (like ICAL.Time)
  @return {?}                An instance of the found type.