.getStatisticScalar(
            statName, refHist);

        if (statScalar !== undefined) {
          data.push({
            x: subRow.name,
            y: statScalar.value,
          });
        }
      }
      if (data.length < 2) return;

      this.overviewChart_ = new tr.ui.b.NameLineChart();
      this.$.overview_container.appendChild(this.overviewChart_);
      this.overviewChart_.displayXInHover = true;
      this.overviewChart_.hideLegend = true;
      this.overviewChart_.unit = unit;
      this