perf(form): don't call $setSubmitted twice for nested child forms

src/ng/directive/form.js

@@ -280,7 +280,7 @@ FormController.prototype = {
     }
 
     forEach(this.$$controls, function(control) {
-      if (control.$setSubmitted) {
+      if (control.$setSubmitted && !control.$submitted) {
         control.$setSubmitted(true);
       }
     });

test/ng/directive/formSpec.js

@@ -541,9 +541,41 @@ describe('form', function() {
           child = scope.child;
 
       parent.$setSubmitted();
+      expect(parent.$submitted).toBeTruthy();
       expect(child.$submitted).toBeTruthy();
     });
 
+    it('should set $submitted to true on child and parent forms when form is submitted', function() {
+      doc = jqLite(
+          '<ng-form name="parent">' +
+            '<ng-form name="child">' +
+              '<ng-form name="grandchild">' +
+                '<input ng:model="modelA" name="inputA">' +
+                '<input ng:model="modelB" name="inputB">' +
+              '</ng-form>' +
+            '</ng-form>' +
+          '</ng-form>');
+      $compile(doc)(scope);
+
+      var parent = scope.parent,
+          child = scope.child,
+          grandchild = scope.grandchild;
+
+      spyOn(parent, '$setSubmitted').and.callThrough();
+      spyOn(child, '$setSubmitted').and.callThrough();
+      spyOn(grandchild, '$setSubmitted').and.callThrough();
+
+      child.$setSubmitted();
+
+      expect(parent.$submitted).toBeTruthy();
+      expect(child.$submitted).toBeTruthy();
+      expect(grandchild.$submitted).toBeTruthy();
+
+      expect(parent.$setSubmitted).toHaveBeenCalledOnce();
+      expect(child.$setSubmitted).toHaveBeenCalledOnce();
+      expect(grandchild.$setSubmitted).toHaveBeenCalledOnce();
+    });
+
     it('should deregister a child form when its DOM is removed', function() {
       doc = jqLite(
         '<form name="parent">' +