Turn on harmony arrays and regexp.

sky/framework/sky-element/sky-element.sky

 <!--
 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 -->
 <import src="sky-binder.sky" as="binder" />
 <script>
 var attributeConverters = {
   boolean: function(value) {
     if (typeof value == 'string')
@@ skipping 59 matching lines @@
     this.attributes = parseAttributeSpec(definition.getAttribute('attributes'));
     this.eventHandlers = collectEventHandlers(definition);
     this.template = definition.querySelector('template');
     Object.preventExtensions(this);
   }
 
   getEventHandler(eventName) {
     return this.definition.getAttribute('on-' + eventName);
   }
 
-  getAttributeNames() {
-    // TODO(esprehn): We can replace this method with
-    // Array.from(registration.attributes) once we turn that on.
-    var names = []
-    this.attributes.forEach(function(converter, name) {
-      names.push(name);
-    });
-    return names;
-  }
-
   synthesizeAttributes(prototype) {
     this.attributes.forEach(function(converter, name) {
       Object.defineProperty(prototype, name, {
         get: function() {
           return converter(this.getAttribute(name));
         },
         set: function(newValue) {
           this.setAttribute(name, converter(newValue));
         },
         enumerable: true,
@@ skipping 22 matching lines @@
 
     if (registrations.has(registration.tagName)) {
       throw new Error('Duplicate registration for tag name: ' +
           registration.tagName);
     }
 
     registration.synthesizeAttributes(this.prototype);
 
     // TODO(esprehn): Combine the two element registries here and in sky binder.
     binder.registerElement(registration.tagName, {
-      attributeNames: registration.getAttributeNames(),
+      attributeNames: Array.from(registration.attributes.keys()),
     });
 
     registrations.set(registration.tagName, registration);
     return document.registerElement(registration.tagName, {
       prototype: this.prototype,
     });
   }
 
   created() {
     // override
@@ skipping 108 matching lines @@
         binding.setValue(this[name]);
         binding.discardChanges();
       }
     }
     this.dirtyPropertyBindings = null;
   }
 };
 
 module.exports = SkyElement;
 </script>