Abort master management if the current hostname doesn't match the master's.

infra/libs/buildbot/master.py

Index: infra/libs/buildbot/master.py
diff --git a/infra/libs/buildbot/master.py b/infra/libs/buildbot/master.py
index ea5040023f8d793dd19279fd44af4e1e3ada04fc..ab87dea922d13c9266bf371c525a3bf6cb9ef246 100644
--- a/infra/libs/buildbot/master.py
+++ b/infra/libs/buildbot/master.py
@@ -93,7 +93,7 @@ def get_last_no_new_builds(directory):
   return last_no_new_builds
 
 
-def _get_mastermap_data(directory):
+def get_mastermap_data(directory):
   """Get mastermap JSON from a master directory."""
 
   build_dir = os.path.join(directory, os.pardir, os.pardir, os.pardir, 'build')
@@ -119,7 +119,7 @@ def _get_mastermap_data(directory):
 
 def _get_master_web_port(directory):
   """Determine the web port of the master running in the given directory."""
-  mastermap_data = _get_mastermap_data(directory)
+  mastermap_data = get_mastermap_data(directory)
   if mastermap_data:
     return mastermap_data['port']
   return None