code: function() {
              var xAxisKey = this.xAxis.getKey(),
                  useTimeNames = (this.processedData.xAxisType === 'time'),
                  resolveLabel = this.getLegendName.bind(this);
              $.extend(true, this.hcConfig, {
                  legend: {
                      labelFormatter: function() {
                          return resolveLabel(this, useTimeNames);
                      }
                  }
              });
          }
docs: override