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

masters/master.client.v8.ports/master.cfg

 # -*- python -*-
 # ex: set syntax=python:
 
 # Copyright 2016 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.
 
 from buildbot.schedulers.basic import SingleBranchScheduler
 
 from master import gitiles_poller
 from master import master_utils
 from master import slaves_list
 from master.factory import annotator_factory
 
 import config
 import master_site_config
 
 ActiveMaster = master_site_config.V8Ports
 MAIL_NOTIFIER = ActiveMaster.is_production_host
 
 # This is the dictionary that the buildmaster pays attention to. We also use
 # a shorter alias to save typing.
 c = BuildmasterConfig = {}
 c['status'] = []
 
 
 ####### DATABASE
 
-config.DatabaseSetup(c, require_dbconfig=ActiveMaster.is_production_host)
+config.DatabaseSetup(c)
 
 
 ####### CHANGESOURCES
 
 comparator = gitiles_poller.GitilesRevisionComparator()
 c['change_source'] = [
   gitiles_poller.GitilesPoller(
       'https://chromium.googlesource.com/v8/v8',
       branches=['master'],
       pollInterval=20,
@@ skipping 233 matching lines @@
   mail_notifier_cfg.Update(config, ActiveMaster, c)
 
 # Adjust the buildCaches to be 3x the number of slaves per builder.
 c['autoBuildCacheRatio'] = 3
 
 
 ####### PROJECT IDENTITY
 
 c['projectName'] = ActiveMaster.project_name
 c['projectURL'] = config.Master.project_url