add: aSink = XPCU.QI(aSink, "nsIRDFXMLSink"); 
context:   onEndLoad: function(aSink)   {     var ds = XPCU.QI(aSink, "nsIRDFDataSource");    this.mListener.onDataSourceReady(ds);    aSink.removeXMLSinkObserver(this);  }
meta: 5872	/local1/tlutelli/issta_data/temp/all_js/javascript/2006_temp/2006/5872/9aa8f51ed41c3048466a084f3b103aa7fd10dc83/RDFU.js/clean/extensions/inspector/resources/content/jsutil/rdf/RDFU.js