B2G/gecko/browser/base/content/test/browser_pluginnotification.js
// closecallback is called when the tab is closed
closecallback is called when the tab is closed
closecallback is called when the tab is closed
function TabOpenListener(url, opencallback, closecallback) {
  this.url = url;
  this.opencallback = opencallback;
  this.closecallback = closecallback;
  gBrowser.tabContainer.addEventListener("TabOpen", this, false);
}
function TabOpenListener ( url , opencallback , closecallback ) { this . url = url ; this . opencallback = opencallback ; this . closecallback = closecallback ; gBrowser . tabContainer . addEventListener ( "TabOpen" , this , false ) ; }
closecallback is called when the tab is closed
closecallback is called when the tab is closed