code: function flushPendingChains() {
        if (pendingQueue.length === 0) { return; } // nothing to do
  
        var queue = pendingQueue;
        pendingQueue = [];
  
        forEach.call(queue, function(q) { q[0].add(q[1]); });
  
        warn('Watching an undefined global, Ember expects watched globals to be setup by the time the run loop is flushed, check for typos', pendingQueue.length === 0);
      }
docs: attempts to add the pendingQueue chains again. If some of them end up back in the queue and reschedule is true, schedules a timeout to try again.