 		private function handleCallLater():void
 		{
 			var maxComputationTime:uint = _deactivatedFrameRate ? _deactivatedMaxComputationTimePerFrame : maxComputationTimePerFrame;
+			if (!_event)
+			{
+				reportError("StageUtils.handleCallLater(): _event is null. This should never happen.");
+				return;
+			}
 			if (_event.type == Event.ENTER_FRAME)
 			{
 				resetDebugTime();

			// The variables countdown and lastPriority are used to avoid running newly-added tasks immediately.
			// This avoids wasting time on async tasks that do nothing and return early, adding themselves back to the queue.

			var args:Array, args2:Array;
			var stackTrace:String;
			var now:int;
			var allStop:int = _currentFrameStartTime + maxComputationTime;

				}
				
				// set event variables
				if (_event != null)
					reportError(StandardLib.substitute(
						'StageUtils: Upon handling an event, the _event variable was non-null.'
						+ ' (event.type == "{0}", _event.type == "{1}").'
						+ ' This should not happen unless the previous event callback threw an error.',
						event.type,
						_event.type
					));
				_event = event;
				_eventTime = getTimer();
				
