function getChildTask({ts, duration, url, eventName}) {
  return {
    name: eventName ?? 'FunctionCall',
    ts: ts * 1000,
    dur: duration * 1000,
    pid,
    tid,
    ph: 'X',
    cat: 'devtools.timeline',
    args: {
      data: {
        url,
        functionName: 'fakeFunction',
      },
    },
  };
}
@param {ChildTaskDef} options
@return {LH.TraceEvent}