Docserver: Make the hand-written Cron methods run first rather than last, since

chrome/common/extensions/docs/server2/sidenav_data_source.py

 # Copyright (c) 2012 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 import copy
 import logging
 
 from compiled_file_system import SingleFile
 from data_source import DataSource
 from future import Gettable, Future
@@ skipping 62 matching lines @@
         if not href.startswith('/'):
           logging.warn('Paths in sidenav must be qualified. %s is not.' % href)
         else:
           href = href.lstrip('/')
         item['href'] = self._server_instance.base_path + href
 
   def Cron(self):
     futures = [
         self._cache.GetFromFile('%s/%s_sidenav.json' % (JSON_PATH, platform))
         for platform in ('apps', 'extensions')]
-    for future in futures:
-      future.Get()
+    return Future(delegate=Gettable(lambda: [f.Get() for f in futures]))
 
   def get(self, key):
     sidenav = copy.deepcopy(self._cache.GetFromFile(
         '%s/%s_sidenav.json' % (JSON_PATH, key)).Get())
     _AddSelected(sidenav, self._server_instance.base_path + self._request.path)
     return sidenav