code: function _delay(tag, ms, callback) {
  		/*jshint -W040:true */
  		var self = this;
  
  		tag = "" + (tag || "default");
  		if (timerMap[tag] != null) {
  			clearTimeout(timerMap[tag]);
  			delete timerMap[tag];
  			// console.log("Cancel timer '" + tag + "'");
  		}
  		if (ms == null || callback == null) {
  			return;
  		}
  		// console.log("Start timer '" + tag + "'");
  		timerMap[tag] = setTimeout(function() {
  			// console.log("Execute timer '" + tag + "'");
  			callback.call(self);
  		}, +ms);
  	}
docs: Invoke callback after `ms` milliseconds.
  Any pending action of this type is cancelled before.