Update to polymer js version 0.4.1

pkg/polymer/lib/src/declaration.dart

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 part of polymer;
 
 /// *Warning* this class is experimental and subject to change.
 ///
 /// The data associated with a polymer-element declaration, if it is backed
 /// by a Dart class instead of a JavaScript prototype.
@@ skipping 444 matching lines @@
       map['$path'.toLowerCase()] = value;
     });
     return map;
   }
 
   void createPropertyAccessors() {
     // Dart note: since we don't have a prototype in Dart, most of the work of
     // createPolymerAccessors is done lazily on the first access of properties.
     // Here we just extract the information from annotations and store it as
     // properties on the declaration.
+
+    // Dart Note: The js side makes computed properties read only, and does
+    // special logic right here for them. For us they are automatically read
+    // only unless you define a setter for them, so we left that out.
     var options = const smoke.QueryOptions(includeInherited: true,
         includeUpTo: HtmlElement, withAnnotations: const [ComputedProperty]);
     var existing = {};
     for (var decl in smoke.query(type, options)) {
       var meta = decl.annotations.firstWhere((e) => e is ComputedProperty);
       var name = decl.name;
       var prev = existing[name];
       // The definition of a child class takes priority.
       if (prev == null || smoke.isSubclassOf(decl.type, prev.type)) {
         _computed[name] = meta.expression;
         existing[name] = decl;
       }
     }
   }
 }
 
 /// maps tag names to prototypes
 final Map _typesByName = new Map<String, Type>();
 
 Type _getRegisteredType(String name) => _typesByName[name];
 
+/// Dart Note: instanceOfType not implemented for dart, its not needed.
+
 /// track document.register'ed tag names and their declarations
 final Map _declarations = new Map<String, PolymerDeclaration>();
 
 bool _isRegistered(String name) => _declarations.containsKey(name);
 PolymerDeclaration _getDeclaration(String name) => _declarations[name];
 
 /// Using Polymer's platform/src/ShadowCSS.js passing the style tag's content.
 void _shimShadowDomStyling(DocumentFragment template, String name,
     String extendee) {
   if (_ShadowCss == null ||!_hasShadowDomPolyfill) return;
@@ skipping 51 matching lines @@
   String name = smoke.symbolToName(symbol);
   if (name == null) return false;
   return name.endsWith('Changed') && name != 'attributeChanged';
 }
 
 
 final _ATTRIBUTES_REGEX = new RegExp(r'\s|,');
 
 final JsObject _Platform = js.context['Platform'];
 final JsObject _Polymer = js.context['Polymer'];