rem: m.addEventListener("command", function() { for (var i = 0; i < undoItems.length; i++) undoCloseTab(); }, false); 
add: function () { return browser.warnAboutClosingTabs(true); }); 
context:   m.addEventListener("command", function() {    for (var i = 0; i < undoItems.length; i++)      undoCloseTab();  }, false);
meta: 10234	/local1/tlutelli/issta_data/temp/all_js/javascript/2007_temp/2007/10234/5a746e48f3be66f2cc2c0ff4a2e723399c01c354/browser.js/buggy/browser/base/content/browser.js