add: if (!parent) { throw Error(gettext("Couldn't find the basic layout. Please choose another one.")); } 
context: Layout.prototype.update = function(data) {   this.title = data.title.trim() || "Layout #" + this._id;   this.description = data.description;   this.copyright = data.copyright;   if (data.parent) {      var parent = root.layouts.getById(data.parent);      if (parent !== this) {         this.parent = parent;      }   }   this.mode = data.mode;   this.touch();   return;};
meta: 993	/local1/tlutelli/issta_data/temp/all_js/javascript/2007_temp/2007/993/83da4c933b2bad9143c64c71f663a04406c91348/Layout.js/buggy/code/Layout/Layout.js