Fix the broken tabs menu in the sidebar, and clean up a related idiom in

the prefs window.  bug 211088: r=rjc, sr=bz, a=asa.

xpfe/components/prefwindow/resources/content/pref-applications.js

@@ -36,8 +36,7 @@ function newType()
   var handlerOverride = new HandlerOverride();
   window.openDialog("chrome://communicator/content/pref/pref-applications-edit.xul", "appEdit", "chrome,modal=yes,resizable=no", handlerOverride);
   if (gNewTypeRV) {
-    //gList.builder.rebuild();
-    gList.setAttribute("ref", "urn:mimetypes");
+    gList.builder.rebuild();
     gNewTypeRV = null;
   }
 }
@@ -58,7 +57,7 @@ function removeType()
     }
   }
   removeOverride(handlerOverride.mimeType);
-  gList.setAttribute("ref", "urn:mimetypes");
+  gList.builder.rebuild();
   selectApplication();
 }
 
@@ -184,8 +183,7 @@ function Startup()
 
   // intialize the listbox
   gList.database.AddDataSource(gDS);
-  gList.removeAttribute("ref"); // Remove the attr so the set is not a no-op
-  gList.setAttribute("ref", "urn:mimetypes");
+  gList.builder.rebuild();
 
   // Test whether the data source is already loaded.
   if (gDS.QueryInterface(Components.interfaces.nsIRDFRemoteDataSource).loaded) {

xpfe/components/sidebar/resources/sidebarOverlay.js

@@ -1240,7 +1240,6 @@ function SidebarShowHide() {
 function SidebarBuildPickerPopup() {
   var menu = document.getElementById('sidebar-panel-picker-popup');
   menu.database.AddDataSource(RDF.GetDataSource(sidebarObj.datasource_uri));
-  menu.setAttribute('ref', sidebarObj.resource);
 
   for (var ii=3; ii < menu.childNodes.length; ii++) {
     var panel_menuitem = menu.childNodes.item(ii);
@@ -1252,6 +1251,7 @@ function SidebarBuildPickerPopup() {
       panel_menuitem.setAttribute('checked', 'true');
     }
   }
+  menu.builder.rebuild();
 }
 
 function SidebarTogglePanel(panel_menuitem) {