Don't require a .dbconfig file on any masters.

masters/master.client.libyuv/master.cfg

 # 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.
 
 # These modules come from scripts/master, which must be in the PYTHONPATH.
 from master import master_utils
 from master import slaves_list
 
 import config
 import master_site_config
 ActiveMaster = master_site_config.Libyuv
 
 c = BuildmasterConfig = {}
 c['change_source'] = []
 c['schedulers'] = []
 c['builders'] = []
 c['status'] = []
 
-config.DatabaseSetup(c, require_dbconfig=ActiveMaster.is_production_host)
+config.DatabaseSetup(c)
 
 import master_source_cfg
 import master_win_cfg
 import master_mac_cfg
 import master_linux_cfg
 import master_android_cfg
 
 master_source_cfg.Update(config, c)
 master_win_cfg.Update(c)
 master_mac_cfg.Update(c)
@@ skipping 32 matching lines @@
 if ActiveMaster.is_production_host:
   from buildbot.status import mail
   lookup = master_utils.FilterDomain(
       permitted_domains=ActiveMaster.permitted_domains)
   c['status'].append(mail.MailNotifier(
       fromaddr=ActiveMaster.from_address,
       extraRecipients=[ActiveMaster.from_address],
       lookup=lookup,
       mode='problem',
       relayhost=config.Master.smtp))