docs: function (sortName, sortKeyGetter) {
                  this.$assert(326, sortName != null && sortKeyGetter != null);
                  if (this.sortOrder != this.SORT_INITIAL && this.sortName == sortName) {
                      if (this.sortOrder == this.SORT_ASCENDING) {
                          this.sortOrder = this.SORT_DESCENDING;
                      } else /* if (this.sortOrder == this.SORT_DESCENDING) */{
                          this.$assert(330, this.sortOrder == this.SORT_DESCENDING);
                          this.sortOrder = this.SORT_ASCENDING;
                      }
                  } else {
                      this.sortName = sortName;
                      this.sortKeyGetter = this.$normCallback(sortKeyGetter);
                      this.sortOrder = this.SORT_ASCENDING;
                  }
              }