anchor.diff:  
     /// Registers getters and setters for all published attributes.
     void _processPolymerElement(Element node) {
  +    // Nothing here applies if inside a polymer js element
  +    if (_inPolymerJs) return;
  +
       var tagName = node.attributes['name'];
       var value = node.attributes['attributes'];
       if (value != null) {
  
positive.code:   /// Produces warnings for misuses of on-foo event handlers, and for instanting
    /// custom tags incorrectly.
    void _processNormalElement(Element node) {
      var tag = node.localName;
      var isCustomTag = isCustomTagName(tag) || node.attributes['is'] != null;
  
  
negative.code:   final _SubExpressionVisitor expressionVisitor;
    final BuildLogger logger;
    bool _inTemplate = false;
    bool _inPolymerJs = false;
  
    _HtmlExtractor(this.logger, this.generator, this.publishedAttributes,
        this.expressionVisitor);
  
    void visitElement(Element node) {
      if (_inTemplate) _processNormalElement(node);
      var lastInPolymerJs = _inPolymerJs;
      if (node.localName == 'polymer-element') {
        // Detect Polymer JS elements, the current logic is any element with only
        // non-dart script tags.
        var scripts = node.querySelectorAll('script');
        _inPolymerJs = scripts.isNotEmpty &&
            scripts.every((s) => s.attributes['type'] != 'application/dart');
        _processPolymerElement(node);
        _processNormalElement(node);
      }
  