code: function ThreadTimeSlice(thread, schedulingState, cat,
                             start, args, opt_duration) {
      Slice.call(this, cat, schedulingState,
                 this.getColorForState_(schedulingState),
          start, args, opt_duration);
      this.thread = thread;
      this.schedulingState = schedulingState;
      this.cpuOnWhichThreadWasRunning = undefined;
    }
docs: A ThreadTimeSlice is a slice of time on a specific thread where that thread
  was running on a specific CPU, or in a specific sleep state.
  
  As a thread switches moves through its life, it sometimes goes to sleep and
  can't run. Other times, its runnable but isn't actually assigned to a CPU.
  Finally, sometimes it gets put on a CPU to actually execute. Each of these
  states is represented by a ThreadTimeSlice:
  
  Sleeping or runnable: cpuOnWhichThreadWasRunning is undefined
  Running:  cpuOnWhichThreadWasRunning is set.
  
  @constructor