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

masters/master.chromiumos.chromium/master.cfg

 # Copyright 2014 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
 
 MASTER='ChromiumOSChromium'
 ActiveMaster = master_site_config.ChromiumOSChromium
 
 # Only the production Chromium Buildbot acts as the tree gatekeeper.
 TREE_GATE_KEEPER = ActiveMaster.is_production_host
 
 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_chromium_cfg
 import master_asan_cfg
 import master_perf_cfg
 
 master_source_cfg.Update(config, ActiveMaster, c)
 master_chromium_cfg.Update(config, ActiveMaster, c)
 master_asan_cfg.Update(config, ActiveMaster, c)
 master_perf_cfg.Update(config, ActiveMaster, c)
@@ skipping 20 matching lines @@
     c['builders'],
     config.Master.GetBotPassword())
 master_utils.VerifySetup(c, slaves)
 
 # Adds common status and tools to this master.
 master_utils.AutoSetupMaster(c, ActiveMaster,
     public_html='../master.chromium/public_html',
     templates=['../master.chromium/templates'],
     tagComparator=getattr(c['change_source'][0], 'comparator', None),
     enable_http_status_push=ActiveMaster.is_production_host)