Use CBE for firefighter

firefighter/update/common/buildbot/network.py

 # Copyright 2015 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 json
 import logging
 
 from google.appengine.api import urlfetch
 from google.appengine.runtime import apiproxy_errors
 
 from base import constants
 
 
-def BuildUrl(master_name, url):
-  return '%s/%s/%s' % (constants.BUILDBOT_BASE_URL, master_name, url)
+def BuildUrl(master_name, url, use_cbe=False):
+  base = constants.BUILDBOT_BASE_URL
+  if use_cbe:
+    base = constants.CBE_BASE_URL + '/p'
+    url += '?json=1'
+
+  return '%s/%s/%s' % (base, master_name, url)
 
 
 def FetchData(url):
   try:
     return json.loads(FetchText(url))
   except ValueError:
     logging.warning('Data is corrupt: %s', url)
     raise
 
 
 def FetchText(url):
   logging.debug('Retrieving %s', url)
   try:
     return urlfetch.fetch(url).content
   except (apiproxy_errors.DeadlineExceededError, urlfetch.DownloadError,
           urlfetch.InternalTransientError):
     # Could be intermittent; try again.
     try:
       return urlfetch.fetch(url).content
     except:
       logging.error('Error retrieving URL: %s', url)
       raise
   except:
     logging.error('Error retrieving URL: %s', url)
     raise