code: function(name, extendee) { 
        var info = {
          prototype: this.prototype
        }
        // native element must be specified in extends
        var typeExtension = this.findTypeExtension(extendee);
        if (typeExtension) {
          info.extends = typeExtension;
        }
        // register the prototype with HTMLElement for name lookup
        HTMLElement.register(name, this.prototype);
        // register the custom type
        this.ctor = document.registerElement(name, info);
      }
docs: register 'prototype' to custom element 'name', store constructor