    tr.b.Unit.byName.timeStampInMs.format(this.start);
    },

    get stableId() {
      const parentAsyncSliceGroup = this.parentContainer.asyncSliceGroup;
      return parentAsyncSliceGroup.stableId + '.' +
          parentAsyncSliceGroup.slices.indexOf(this);
    },

    * findTopmostSlicesRelativeToThisSlice(eventPredicate, opt_this) {
      if (eventPredicate(this)) {
        yield this;
        return;
      }
      for (const s of this.subSlices) {
        yield* s.findTopmostSlicesRelativeToThisSli