close window on receipt of close event, as well as destroy. synchs with recent changes to gtk/mac/win windows. fixes bug 20811. r:troy a:chofmann

webshell/tests/viewer/nsBrowserWindow.cpp

@@ -321,6 +321,7 @@ HandleBrowserEvent(nsGUIEvent *aEvent)
       result = nsEventStatus_eConsumeNoDefault;
       break;
 
+    case NS_XUL_CLOSE:
     case NS_DESTROY:
     {
       nsViewerApp* app = bw->mApp;