add: if (index < 0) return;  
context: function EnsureRowInThreadOutlinerIsVisible(index){  var outliner = GetThreadOutliner();  outliner.boxObject.QueryInterface(Components.interfaces.nsIOutlinerBoxObject).ensureRowIsVisible(index); }
meta: 10234	/local1/tlutelli/issta_data/temp/all_js/javascript/2006_temp/2006/10234/ee85e50aeddd27ed604bbc6edc696a0605b41feb/threadPane.js/clean/mailnews/base/resources/content/threadPane.js