code: function(elementElement) {
        var template = this.fetchTemplate(elementElement);
        if (template) {
          var root = this.shadowFromTemplate(template);
          this.shadowRoots[elementElement.name] = root;
        }
      }
docs: Perform init-time actions based on static information in the
  `<polymer-element>` instance argument.
  
  For example, the standard implementation locates the template associated
  with the given `<polymer-element>` and stamps it into a shadow-root to
  implement shadow inheritance.
  
  An element may override this method for custom behavior.
  
  @method parseDeclaration