// An Executor that can be used to execute tasks in parallel.
 // An Executor that executes tasks one at a time in serial order.  This
 // serialization is global to a particular process.
 public virtual void Execute(Runnable r)
 {
     lock (this)
     {
         mTasks.Offer(new _Runnable_58(this, r));
         if (mActive == null)
         {
             ScheduleNext();
         }
     }
 }