Break config_default into master_site_configs.

masters/master.client.sfntly/master.cfg

Index: masters/master.client.sfntly/master.cfg
diff --git a/masters/master.client.sfntly/master.cfg b/masters/master.client.sfntly/master.cfg
index c8433d828246517403eb8721e3217019eb52d8e1..eac4e895751effec15bdbafe4077fc9f072dea73 100644
--- a/masters/master.client.sfntly/master.cfg
+++ b/masters/master.client.sfntly/master.cfg
@@ -5,6 +5,7 @@
 # 'master.cfg' in your buildmaster's base directory.
 
 import config
+import master_site_config
 
 # This is the dictionary that the buildmaster pays attention to. We also use
 # a shorter alias to save typing.
@@ -279,7 +280,7 @@ c['schedulers'] = [
 
 ####### BUILDSLAVES
 
-ActiveMaster = config.Master.Sfntly
+ActiveMaster = master_site_config.Sfntly
 
 # The 'slaves' list defines the set of allowable buildslaves. List all the
 # slaves registered to a builder. Remove dupes.
@@ -289,7 +290,7 @@ c['slaves'] = master_utils.AutoSetupSlaves(c['builders'],
 # Make sure everything works together.
 master_utils.VerifySetup(c, slaves)
 
-ActiveMaster = config.Master.Sfntly
+ActiveMaster = master_site_config.Sfntly
 c['projectName'] = ActiveMaster.project_name
 c['projectURL'] = ActiveMaster.project_url
 c['buildbotURL'] = 'http://build.chromium.org/p/client.sfntly/'