        this.sortedTasks_[this.lastTaskIndex_]);
      }
      return firstTaskEQT + this.innerEQT_ + lastTaskEQT;
    }

    /**
     * Moves the window to the given time t.
     * @param {number} The time.
     */
    slide(t) {
      this.range_ = tr.b.math.Range.fromExplicitRange(t, t + this.windowSize_);
      if (this.firstTaskIndex_ < this.sortedTasks_.length &&
          this.sortedTasks_[this.firstTaskIndex_].end <= t) {
        // The first task moved out of the window.
        this.firstTaskIndex