Update from https://crrev.com/327068

testing/legion/common_lib.py

 # Copyright 2015 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.
 
 """Common library methods used by both coordinator and task machines."""
 
 import argparse
 import logging
 import os
 import socket
 import xmlrpclib
 
 LOGGING_LEVELS = ['DEBUG', 'INFO', 'WARNING', 'WARN', 'ERROR']
 MY_IP = socket.gethostbyname(socket.gethostname())
 SERVER_ADDRESS = ''
 SERVER_PORT = 31710
 DEFAULT_TIMEOUT_SECS = 20 * 60  # 30 minutes
 THIS_DIR = os.path.dirname(os.path.abspath(__file__))
 SWARMING_DIR = os.path.join(THIS_DIR, '..', '..', 'tools', 'swarming_client')
 
 
 def InitLogging():
   """Initialize the logging module.
 
   Raises:
     argparse.ArgumentError if the --verbosity arg is incorrect.
   """
   parser = argparse.ArgumentParser()
-  logging_action = parser.add_argument('--verbosity', default='ERROR')
+  logging_action = parser.add_argument('--verbosity', default='INFO')
   args, _ = parser.parse_known_args()
   if args.verbosity not in LOGGING_LEVELS:
     raise argparse.ArgumentError(
         logging_action, 'Only levels %s supported' % str(LOGGING_LEVELS))
   logging.basicConfig(
       format='%(asctime)s %(filename)s:%(lineno)s %(levelname)s] %(message)s',
       datefmt='%H:%M:%S', level=args.verbosity)
 
 
 def ConnectToServer(server):
   """Connect to an RPC server."""
   addr = 'http://%s:%d' % (server, SERVER_PORT)
   logging.debug('Connecting to RPC server at %s', addr)
-  return xmlrpclib.Server(addr)
+  return xmlrpclib.Server(addr, allow_none=True)