An idle task doesn't do any work itself but cycles control between the two
device tasks.
@param {Scheduler} scheduler the scheduler that manages this task
@param {int} v1 a seed value that controls how the device tasks are scheduled
@param {int} count the number of times this task should be scheduled
@constructor
function IdleTask(scheduler, v1, count) {
  this.scheduler = scheduler;
  this.v1 = v1;
  this.count = count;
}