!== undefined) {
          this.$.overview_container.removeChild(this.overviewChart_);
          this.overviewChart_ = undefined;
        }
        this.showOverview();
      }
    },

    onClick_(event) {
      // Since the histogram-set-table's table doesn't support any kind of
      // selection, clicking anywhere within a row that has subRows will
      // expand/collapse that row, which can relayout the table and move things
      // around. Prevent table relayout by preventing the tr-ui-b-table from
