r). We cannot define a proper
        // task window in this case to calculate Estimated Input Latency.
        throw Error('Encountered two consecutive interactive timestamps ' +
            'with no navigationStart between them. ' +
            'PostInteractiveTaskWindow is not well defined in this case.');
      }

      taskWindows.push(tr.b.math.Range.fromExplicitRange(
          currTTI, taskWindowEndTs));
      lastTaskWindowEndTs = taskWindowEndTs;
    }
    return taskWindows;
  }

  /**
   * Retur