code: function(guid, array) {
          collection.requestMap[guid] = {
            array: array,
            dict: _.object(_.map(array, function(id) { return [id, id]; }))
          };
        }
docs: ************* PRIVATE METHODS ************// 
  @private
  @method cacheMixin.setRequestedIds
  @param guid {String} the global unique identifier for the requester
  @param array {Array} the array of ids the requester wants