Add FormData wrapper

Fixes Polymer/polymer#587

build.json

@@ -45,5 +45,6 @@
   "src/wrappers/Document.js",
   "src/wrappers/Window.js",
   "src/wrappers/DataTransfer.js",
+  "src/wrappers/FormData.js",
   "src/wrappers/override-constructors.js"
 ]

shadowdom.js

@@ -61,6 +61,7 @@
     'src/wrappers/Document.js',
     'src/wrappers/Window.js',
     'src/wrappers/DataTransfer.js',
+    'src/wrappers/FormData.js',
     'src/wrappers/override-constructors.js'
   ].forEach(function(src) {
     document.write('<script src="' + base + src + '"></script>');

src/wrappers/FormData.js

@@ -0,0 +1,23 @@
+/**
+ * Copyright 2014 The Polymer Authors. All rights reserved.
+ * Use of this source code is goverened by a BSD-style
+ * license that can be found in the LICENSE file.
+ */
+
+(function(scope) {
+  'use strict';
+
+  var registerWrapper = scope.registerWrapper;
+  var unwrap = scope.unwrap;
+
+  var OriginalFormData = window.FormData;
+
+  function FormData(formElement) {
+    this.impl = new OriginalFormData(formElement && unwrap(formElement));
+  }
+
+  registerWrapper(OriginalFormData, FormData, new OriginalFormData());
+
+  scope.wrappers.FormData = FormData;
+
+})(window.ShadowDOMPolyfill);

test/js/FormData.js

@@ -0,0 +1,20 @@
+/*
+ * Copyright 2014 The Polymer Authors. All rights reserved.
+ * Use of this source code is goverened by a BSD-style
+ * license that can be found in the LICENSE file.
+ */
+
+suite('FormData', function() {
+
+  test('instanceof', function() {
+    var fd = new FormData();
+    assert.instanceOf(fd, FormData);
+  });
+
+  test('form element', function() {
+    var formElement = document.createElement('form');
+    var fd = new FormData(formElement)
+    assert.instanceOf(fd, FormData);
+  });
+
+});

test/test.main.js

@@ -78,6 +78,7 @@ var modules = [
   'DOMTokenList.js',
   'Document.js',
   'Element.js',
+  'FormData.js',
   'HTMLAudioElement.js',
   'HTMLBodyElement.js',
   'HTMLButtonElement.js',