code: function(key, silent) {
              this._configs = this._configs || {};
              var configs = this._configs;
              
              key = ( ( Lang.isString(key) ) ? [key] : key ) || 
                      this.getAttributeKeys();
              
              for (var i = 0, len = key.length; i < len; ++i) { 
                  if (configs.hasOwnProperty(key[i])) {
                      this._configs[key[i]].refresh(silent);
                  }
              }
          }
docs: Sets the attribute's value to its current value.
  @method refresh
  @param {String | Array} key The attribute(s) to refresh
  @param {Boolean} silent Whether or not to suppress change events