refactor($animate): avoid unnecessary lookup

Closes #14902

Author: gkalpak

src/ngAnimate/animateQueue.js

@@ -287,11 +287,10 @@ var $$AnimateQueueProvider = ['$animateProvider', function($animateProvider) {
             bool = animationsEnabled = !!element;
           } else {
             var node = getDomNode(element);
-            var recordExists = disabledElementsLookup.get(node);
 
             if (argCount === 1) {
               // (element) - Element getter
-              bool = !recordExists;
+              bool = !disabledElementsLookup.get(node);
             } else {
               // (element, bool) - Element setter
               disabledElementsLookup.put(node, !bool);