docs: function Thread(parent, tid) {
      if (!parent)
        throw new Error('Parent must be provided.');
  
      tr.model.EventContainer.call(this);
      this.parent = parent;
      this.sortIndex = 0;
      this.tid = tid;
      this.name = undefined;
      this.samples_ = undefined; // Set during createSubSlices
  
      var that = this;
  
      this.sliceGroup = new SliceGroup(this, ThreadSlice, 'slices');
      this.timeSlices = undefined;
      this.kernelSliceGroup = new SliceGroup(
          this, ThreadSlice, 'kernel-slices');
      this.asyncSliceGroup = new AsyncSliceGroup(this, 'async-slices');
    }