Merge pull request #10024 from MarcelGerber/event-chaining-fix

Fix event chaining with .off()

Author: zaggino

src/utils/EventDispatcher.js

@@ -127,13 +127,13 @@ define(function (require, exports, module) {
      * @param {?function(!{type:string, target:!Object}, ...)} fn
      */
     var off = function (events, fn) {
-        var eventsList = events.split(/\s+/).map(splitNs),
-            i;
-        
         if (!this._eventHandlers) {
-            return;
+            return this;
         }
 
+        var eventsList = events.split(/\s+/).map(splitNs),
+            i;
+        
         var removeAllMatches = function (eventRec, eventName) {
             var handlerList = this._eventHandlers[eventName],
                 k;