           ]
   *       |        [     B    ]           [   C    ]   |
   *       |        |   [ D  ] |           |        |   |
   *       |        |          |           |        |   |
   *       v        v          v           v        v   v
   *  Ts : 0        50         80   100   150      180  200
   * RoI :                           [                  ]
   *
   * Total self time for A within |rangeOfInterest| is 100 - 30 = 70.
   *
   * @param {!tr.b.Event} event
   * @param {!tr.b.math.Range} rangeO