Minor lint tweaks and rules cleanup

js/src/util.js

@@ -34,7 +34,7 @@ function getSpecialTransitionEndEvent() {
       if ($(event.target).is(this)) {
         return event.handleObj.handler.apply(this, arguments) // eslint-disable-line prefer-rest-params
       }
-      return undefined // eslint-disable-line no-undefined
+      return undefined
     }
   }
 }