[FIX] don't blow up when there are no records in the theeview

bzr revid: xmo@openerp.com-20110809154817-w9hvt2whhzh5djoz

addons/base/static/src/js/view_tree.js

@@ -94,7 +94,9 @@ openerp.base.TreeView = openerp.base.View.extend({
                     .appendTo($select);
             });
 
-            $select.change();
+            if (!_.isEmpty(records)) {
+                $select.change();
+            }
         });
     },
     /**