fix(ngAria): remove tabindex from radio buttons

Closes angular#12492

Author: marcysutton

src/ngAria/aria.js

@@ -53,15 +53,15 @@ var ngAriaModule = angular.module('ngAria', ['ng']).
                         provider('$aria', $AriaProvider);
 
 /**
-* Internal Utilities 
+* Internal Utilities
 */
 var nodeBlackList = ['BUTTON', 'A', 'INPUT', 'TEXTAREA', 'SELECT', 'DETAILS', 'SUMMARY'];
 
-var isNodeOneOf = function (elem, nodeTypeArray) {
+var isNodeOneOf = function(elem, nodeTypeArray) {
   if (nodeTypeArray.indexOf(elem[0].nodeName) !== -1) {
     return true;
   }
-}
+};
 /**
  * @ngdoc provider
  * @name $ariaProvider
@@ -235,7 +235,8 @@ ngAriaModule.directive('ngShow', ['$aria', function($aria) {
           }
         },
         post: function(scope, elem, attr, ngModel) {
-          var needsTabIndex = shouldAttachAttr('tabindex', 'tabindex', elem);
+          var needsTabIndex = shouldAttachAttr('tabindex', 'tabindex', elem)
+                                && !isNodeOneOf(elem, nodeBlackList);
 
           function ngAriaWatchModelValue() {
             return ngModel.$modelValue;

test/ngAria/ariaSpec.js

@@ -628,6 +628,13 @@ describe('$aria', function() {
       expectAriaAttrOnEachElement(element, 'tabindex', undefined);
     });
 
+    it('should not attach to native controls via ngmodel', function() {
+      scope.$apply('val = null');
+      compileElement('<input type="radio" name="value" value="1" ng-model="val">');
+
+      expect(element.attr('tabindex')).toBeUndefined();
+    });
+
     it('should not attach to random ng-model elements', function() {
       compileElement('<div ng-model="val"></div>');
       expect(element.attr('tabindex')).toBeUndefined();