fix(angular.element): do not break on cleanData() if _data() returns undefined

src/Angular.js

@@ -1909,7 +1909,7 @@ function bindJQuery() {
   jqLite.cleanData = function(elems) {
     var events;
     for (var i = 0, elem; (elem = elems[i]) != null; i++) {
-      events = jqLite._data(elem).events;
+      events = (jqLite._data(elem) || {}).events;
       if (events && events.$destroy) {
         jqLite(elem).triggerHandler('$destroy');
       }

test/jqLiteSpec.js

@@ -501,6 +501,12 @@ describe('jqLite', function() {
       expect(jqLite(c).data('prop')).toBeUndefined();
     });
 
+    it('should not break on cleanData(), if element has no data', function() {
+      var selected = jqLite([a, b, c]);
+      spyOn(jqLite, '_data').and.returnValue(undefined);
+      expect(function() { jqLite.cleanData(selected); }).not.toThrow();
+    });
+
 
     it('should add and remove data on SVGs', function() {
       var svg = jqLite('<svg><rect></rect></svg>');