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

scripts/master/master_gen.py

 # 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.
 
 import ast
 import os
 
 from buildbot.changes.filter import ChangeFilter
 from buildbot.schedulers.basic import SingleBranchScheduler
 from buildbot.schedulers.timed import Nightly
@@ skipping 22 matching lines @@
 def _Populate(BuildmasterConfig, builders, active_master_cls):
   m_annotator = annotator_factory.AnnotatorFactory(active_master_cls)
 
   c = BuildmasterConfig
   c['logCompressionLimit'] = False
   c['projectName'] = active_master_cls.project_name
   c['projectURL'] = Master.project_url
   c['buildbotURL'] = active_master_cls.buildbot_url
 
   # This sets c['db_url'] to the database connect string in found in
-  # the .dbconfig in the master directory, if it exists. If this is
-  # a production host, it must exist.
-  chromium_utils.DatabaseSetup(
-      c,
-      require_dbconfig=active_master_cls.is_production_host)
+  # the .dbconfig in the master directory, if it exists.
+  chromium_utils.DatabaseSetup(c)
 
   c['builders'] = _ComputeBuilders(builders, m_annotator, active_master_cls)
 
   c['schedulers'] = _ComputeSchedulers(builders)
 
   c['change_source'], tag_comparator = _ComputeChangeSourceAndTagComparator(
       builders)
 
   # The 'slaves' list defines the set of allowable buildslaves. List all the
   # slaves registered to a builder. Remove dupes.
@@ skipping 179 matching lines @@
         pollInterval=300,
         revlinktmpl=rev_link_template))
 
   # We have to set the tag_comparator to something, but if we have multiple
   # repos, the tag_comparator will not work properly (it's meaningless).
   # It's not clear if there's a good answer to this.
   if change_source:
     tag_comparator = change_source[0].comparator
 
   return change_source, tag_comparator