      }
    }
    return chromeBounds;
  }

  /**
   * Adds the power histograms to the histogram set.
   *
   * Each power histogram is based on a specific time interval, and is named as
   * follows:
   *
   * - [time_interval_name]:power, which contains a sample for each power
   *    sample data point during any time interval with the given type. Each
   *    sample represents the power draw during the period covered by that
   *    power sample.
   *
   * - [time_interval_name]:energy, which contains a