Fetch all refs, not just refs/heads/master.

git_tools.py

 #!/usr/bin/python
 # Copyright (c) 2012 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.
 
 
 import os
 import re
 import subprocess
 import threading
@@ skipping 64 matching lines @@
   cmd = 'clone%s %s %s' % (' --mirror' if is_mirror else '', git_url, git_repo)
   if not is_mirror and not os.path.exists(git_repo):
     os.makedirs(git_repo)
   return Git(git_repo, cmd, is_mirror)
 
 
 def Fetch(git_repo, git_url, is_mirror):
   """Fetch the latest objects for a given git repository."""
   # Always update the upstream url
   Git(git_repo, 'config remote.origin.url %s' % git_url)
-  Git(git_repo, 'fetch origin +refs/heads/master', is_mirror)
+  Git(git_repo, 'fetch origin', is_mirror)
 
 
 def Ping(git_repo):
   """Confirm that a remote repository URL is valid."""
   status, _ = GetStatusOutput('git ls-remote ' + git_repo)
   return status == 0
 
 
 def CreateLessThanOrEqualRegex(number):
   """ Return a regular expression to test whether an integer less than or equal
@@ skipping 66 matching lines @@
   (_, output) = Git(git_repo, ('log -E --grep=".*git-svn-id:.*@%s " '
                                '-1 --format=%%H %s') % (regex, refspec),
                     is_mirror)
   if output != '':
     output = output.splitlines()[0]
 
   print '%s: %s <-> %s' % (git_repo, output, svn_rev)
   if re.match('^[0-9a-fA-F]{40}$', output):
     return output
   raise Exception('Cannot find revision %s in %s' % (svn_rev, git_repo))