Build shadow_dom package in dart/pkg

pkg/shadow_dom/lib/src/platform/patches-shadowdom-polyfill.js

Index: pkg/shadow_dom/lib/src/platform/patches-shadowdom-polyfill.js
diff --git a/pkg/shadow_dom/lib/src/platform/patches-shadowdom-polyfill.js b/pkg/shadow_dom/lib/src/platform/patches-shadowdom-polyfill.js
new file mode 100644
index 0000000000000000000000000000000000000000..cafb59787c8b4ed488c191d2fe42206574524abc
--- /dev/null
+++ b/pkg/shadow_dom/lib/src/platform/patches-shadowdom-polyfill.js
@@ -0,0 +1,59 @@
+/*
+ * Copyright 2013 The Polymer Authors. All rights reserved.
+ * Use of this source code is governed by a BSD-style
+ * license that can be found in the LICENSE file.
+ */
+(function() {
+  var ShadowDOMPolyfill = window.ShadowDOMPolyfill;
+  var wrap = ShadowDOMPolyfill.wrap;
+
+  // patch in prefixed name
+  Object.defineProperties(HTMLElement.prototype, {
+    //TODO(sjmiles): review accessor alias with Arv
+    webkitShadowRoot: {
+      get: function() {
+        return this.shadowRoot;
+      }
+    }
+  });
+
+  //TODO(sjmiles): review method alias with Arv
+  HTMLElement.prototype.webkitCreateShadowRoot =
+      HTMLElement.prototype.createShadowRoot;
+
+  // TODO(jmesserly): we need to wrap document somehow (a dart:html hook?)
+  window.dartExperimentalFixupGetTag = function(originalGetTag) {
+    var NodeList = ShadowDOMPolyfill.wrappers.NodeList;
+    var ShadowRoot = ShadowDOMPolyfill.wrappers.ShadowRoot;
+    var isWrapper = ShadowDOMPolyfill.isWrapper;
+    var unwrap = ShadowDOMPolyfill.unwrap;
+    function getTag(obj) {
+      if (obj instanceof NodeList) return 'NodeList';
+      if (obj instanceof ShadowRoot) return 'ShadowRoot';
+      if (obj instanceof MutationRecord) return 'MutationRecord';
+      if (obj instanceof MutationObserver) return 'MutationObserver';
+
+      if (isWrapper(obj)) {
+        obj = unwrap(obj);
+
+        // Fix up class names for Firefox. For some of them like
+        // HTMLFormElement and HTMLInputElement, the "constructor" property of
+        // the unwrapped nodes points at the wrapper for some reason.
+        // TODO(jmesserly): figure out why this is happening.
+        var ctor = obj.constructor;
+        if (ctor && ctor._ShadowDOMPolyfill$isGeneratedWrapper) {
+          var name = ctor._ShadowDOMPolyfill$cacheTag_;
+          if (!name) {
+            name = Object.prototype.toString.call(obj);
+            name = name.substring(8, name.length - 1);
+            ctor._ShadowDOMPolyfill$cacheTag_ = name;
+          }
+          return name;
+        }
+      }
+      return originalGetTag(obj);
+    }
+
+    return getTag;
+  };
+})();