Update subprocess2.check_output() to behave like subprocess.check_output().

checkout.py

 # coding=utf8
 # 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.
 """Manages a project checkout.
 
 Includes support for svn, git-svn and git.
 """
 
 from __future__ import with_statement
@@ skipping 122 matching lines @@
 
           filepath = os.path.join(self.project_path, p.filename)
           if p.is_binary:
             with open(filepath, 'wb') as f:
               f.write(p.get())
           else:
             if p.diff_hunks:
               stdout = subprocess2.check_output(
                   ['patch', '-p%s' % p.patchlevel],
                   stdin=p.get(),
+                  stderr=subprocess2.STDOUT,
                   cwd=self.project_path)
             elif p.is_new and not os.path.exists(filepath):
               # There is only a header. Just create the file.
               open(filepath, 'w').close()
         for post in (self.post_processors or []):
           post(self, p)
       except OSError, e:
         raise PatchApplicationFailed(p.filename, '%s%s' % (stdout, e))
       except subprocess.CalledProcessError, e:
         raise PatchApplicationFailed(
@@ skipping 58 matching lines @@
     return subprocess2.check_call_out(
         self._add_svn_flags(args, False), **kwargs)
 
   def _check_output_svn(self, args, credentials=True, **kwargs):
     """Runs svn and throws an exception if the command failed.
 
      Returns the output.
     """
     kwargs.setdefault('cwd', self.project_path)
     return subprocess2.check_output(
-        self._add_svn_flags(args, True, credentials), **kwargs)
+        self._add_svn_flags(args, True, credentials),
+        stderr=subprocess2.STDOUT,
+        **kwargs)
 
   @staticmethod
   def _parse_svn_info(output, key):
     """Returns value for key from svn info output.
 
     Case insensitive.
     """
     values = {}
     key = key.lower()
     for line in output.splitlines(False):
@@ skipping 257 matching lines @@
     return subprocess2.check_call_out(['git'] + args, **kwargs)
 
   def _call_git(self, args, **kwargs):
     """Like check_call but doesn't throw on failure."""
     kwargs.setdefault('cwd', self.project_path)
     kwargs.setdefault('stdout', self.VOID)
     return subprocess2.call(['git'] + args, **kwargs)
 
   def _check_output_git(self, args, **kwargs):
     kwargs.setdefault('cwd', self.project_path)
-    return subprocess2.check_output(['git'] + args, **kwargs)
+    return subprocess2.check_output(
+        ['git'] + args, stderr=subprocess2.STDOUT, **kwargs)
 
   def _branches(self):
     """Returns the list of branches and the active one."""
     out = self._check_output_git(['branch']).splitlines(False)
     branches = [l[2:] for l in out]
     active = None
     for l in out:
       if l.startswith('*'):
         active = l[2:]
         break
@@ skipping 197 matching lines @@
         user, message))
     return 'FAKE'
 
   @property
   def project_name(self):
     return self.checkout.project_name
 
   @property
   def project_path(self):
     return self.checkout.project_path