Use subprocess2 so check_call() can be use consistently in presubmit checks.

presubmit_support.py

 #!/usr/bin/env python
 # Copyright (c) 2011 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.
 
 """Enables directory-specific presubmit checks to run at upload and/or commit.
 """
 
 __version__ = '1.5'
 
 # TODO(joi) Add caching where appropriate/needed. The API is designed to allow
 # caching (between all different invocations of presubmit scripts for a given
 # change). We should add it as our presubmit scripts start feeling slow.
 
 import cPickle  # Exposed through the API.
 import cStringIO  # Exposed through the API.
 import exceptions
 import fnmatch
 import glob
 import logging
 import marshal  # Exposed through the API.
 import optparse
 import os  # Somewhat exposed through the API.
 import pickle  # Exposed through the API.
 import random
 import re  # Exposed through the API.
-import subprocess  # Exposed through the API.
 import sys  # Parts exposed through API.
 import tempfile  # Exposed through the API.
 import time
 import traceback  # Exposed through the API.
 import types
 import unittest  # Exposed through the API.
 import urllib2  # Exposed through the API.
 from warnings import warn
 
 try:
   import simplejson as json  # pylint: disable=F0401
 except ImportError:
   try:
     import json  # pylint: disable=F0401
   except ImportError:
     # Import the one included in depot_tools.
     sys.path.append(os.path.join(os.path.dirname(__file__), 'third_party'))
     import simplejson as json  # pylint: disable=F0401
 
 # Local imports.
 import fix_encoding
 import gclient_utils
 import owners
 import presubmit_canned_checks
 import scm
+import subprocess2 as subprocess  # Exposed through the API.
 
 
 # Ask for feedback only once in program lifetime.
 _ASKED_FOR_FEEDBACK = False
 
 
 class NotImplementedException(Exception):
   """We're leaving placeholders in a bunch of places to remind us of the
   design of the API, but we have not implemented all of it yet. Implement as
   the need arises.
@@ skipping 1129 matching lines @@
                               sys.stdout,
                               sys.stdin,
                               options.default_presubmit,
                               options.may_prompt)
   return not results.should_continue()
 
 
 if __name__ == '__main__':
   fix_encoding.fix_encoding()
   sys.exit(Main(None))