fix($animateCss): do not throw errors when a closing timeout is fired on a removed element

Closes angular#12650

Author: matsko

src/ngAnimate/animateCss.js

@@ -895,10 +895,16 @@ var $AnimateCssProvider = ['$animateProvider', function($animateProvider) {
 
         function onAnimationExpired() {
           var animationsData = element.data(ANIMATE_TIMER_KEY);
-          for (var i = 1; i < animationsData.length; i++) {
-            animationsData[i]();
+
+          // this will be false in the event that the element was
+          // removed from the DOM (via a leave animation or something
+          // similar)
+          if (animationsData) {
+            for (var i = 1; i < animationsData.length; i++) {
+              animationsData[i]();
+            }
+            element.removeData(ANIMATE_TIMER_KEY);
           }
-          element.removeData(ANIMATE_TIMER_KEY);
         }
 
         function onAnimationProgress(event) {

test/ngAnimate/animateCssSpec.js

@@ -1198,6 +1198,24 @@ describe("ngAnimate $animateCss", function() {
             return animator;
           }
         }));
+
+        it("should not throw an error any pending timeout requests resolve after the element has already been removed",
+          inject(function($animateCss, $$body, $rootElement, $timeout, $animate) {
+
+          var element = jqLite('<div></div>');
+          $rootElement.append(element);
+          $$body.append($rootElement);
+
+          ss.addRule('.red', 'transition:1s linear all;');
+
+          $animateCss(element, { addClass: 'red' }).start();
+          triggerAnimationStartFrame();
+          element.remove();
+
+          expect(function() {
+            $timeout.flush();
+          }).not.toThrow();
+        }));
       });
 
       describe("getComputedStyle", function() {