Fix type error

www/common/drive-ui.js

@@ -2820,7 +2820,7 @@ define([
             var getProp = function (el) {
                 if (folder && root[el] && manager.isSharedFolder(root[el])) {
                     var title = manager.getSharedFolderData(root[el]).title || el;
-                    return title.toLowerCase();
+                    return String(title).toLowerCase();
                 } else if (folder) {
                     return el.toLowerCase();
                 }

www/common/proxy-manager.js

@@ -1256,7 +1256,7 @@ define([
 
     var getTitle = function (Env, id, type) {
         var uo = _getUserObjectFromId(Env, id);
-        return uo.getTitle(id, type);
+        return String(uo.getTitle(id, type));
     };
 
     var isReadOnlyFile = function (Env, id) {