function getTopLevelTask({ts, duration}) {
  return {
    name: 'RunTask',
    ts: ts * 1000,
    dur: duration * 1000,
    pid,
    tid,
    ph: 'X',
    cat: 'disabled-by-default-devtools.timeline',
    args: {},
  };
}
@param {TopLevelTaskDef} options
@return {LH.TraceEvent}