Do not assume gclient is in the PATH.

apply_issue.py

 #!/usr/bin/env 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.
 
 """Applies an issue from Rietveld.
 """
 
 import getpass
 import logging
 import optparse
 import os
 import subprocess
 import sys
 import urllib2
 
 import breakpad  # pylint: disable=W0611
 
 import checkout
 import fix_encoding
 import gclient_utils
 import rietveld
 import scm
 
+BASE_DIR = os.path.dirname(os.path.abspath(__file__))
+
 
 def main():
   parser = optparse.OptionParser(description=sys.modules[__name__].__doc__)
   parser.add_option(
       '-v', '--verbose', action='count', default=0,
       help='Prints debugging infos')
   parser.add_option(
       '-e',
       '--email',
       help='IGNORED: Kept for compatibility.')
@@ skipping 77 matching lines @@
     print >> sys.stderr, str(e)
     return 1
 
   if 'DEPS' in map(os.path.basename, patchset.filenames):
     gclient_root = gclient_utils.FindGclientRoot(options.root_dir)
     if gclient_root and scm_type:
       print(
           'A DEPS file was updated inside a gclient checkout, running gclient '
           'sync.')
       base_rev = 'BASE' if scm_type == 'svn' else 'HEAD'
+      gclient_path = os.path.join(BASE_DIR, 'gclient')
+      if sys.platform == 'win32':
+        gclient_path += '.bat'
       return subprocess.call(
-          ['gclient', 'sync', '--revision', base_rev], cwd=gclient_root)
+          [gclient_path, 'sync', '--revision', base_rev], cwd=gclient_root)
   return 0
 
 
 if __name__ == "__main__":
   fix_encoding.fix_encoding()
   sys.exit(main())