lection_.length))));
      histogram.customizeSummaryOptions({
        sum: false,
        percentile: [0.5, 0.9],
      });
      for (const slice of this.currentSelection_) {
        histogram.addSample(slice[selectedKey],
            buildDiagnostics_(slice));
      }

      return histogram;
    },

    updateContents_() {
      const selection = this.currentSelection_;
      if (!selection) return;

      const eventsByTitle = selection.getEventsOrganizedByTitle();
      const numTitles = Object.keys(e