Break config_default into master_site_configs.

masters/master.tryserver.chromium.linux/master_site_config.py

Index: masters/master.tryserver.chromium.linux/master_site_config.py
diff --git a/masters/master.tryserver.chromium.linux/master_site_config.py b/masters/master.tryserver.chromium.linux/master_site_config.py
index c556766b82882f8ae1af672c06621807d9fa6e73..4d48ffb18cb389b19bcfb64bcfad8fb6f02ddde2 100644
--- a/masters/master.tryserver.chromium.linux/master_site_config.py
+++ b/masters/master.tryserver.chromium.linux/master_site_config.py
@@ -4,21 +4,9 @@
 
 """Linux Tryserver definition."""
 
-import socket
+from config import Master
 
-
-class _Master4(object):
-  """Try server master."""
-  master_host = 'master4.golo.chromium.org'
-  is_production_host = socket.getfqdn() == 'master4.golo.chromium.org'
-  tree_closing_notification_recipients = []
-  from_address = 'tryserver@chromium.org'
-  code_review_site = 'https://chromiumcodereview.appspot.com'
-  buildslave_version = 'buildbot_slave_8_4'
-  twisted_version = 'twisted_10_2'
-
-
-class TryServerLinux(_Master4):
+class TryServerLinux(Master.Master4):
   project_name = 'chromium.tryserver.linux'
   master_port = 8045
   slave_port = 8145
@@ -29,4 +17,4 @@ class TryServerLinux(_Master4):
   tree_status_url = base_app_url + '/status'
   store_revisions_url = base_app_url + '/revisions'
   last_good_url = base_app_url + '/lkgr'
-  svn_url = 'svn://svn.chromium.org/chrome-try/try'
+  svn_url = 'svn://svn.chromium.org/chrome-try/try'