Fix git cl upload --squash (for Gerrit).

git_cl.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.
 
 # Copyright (C) 2008 Evan Martin <martine@danga.com>
 
 """A git-command for integrating reviews on Rietveld."""
 
 from distutils.version import LooseVersion
@@ skipping 2011 matching lines @@
         change_desc.prompt()
 
       if CHANGE_ID not in change_desc.description:
         # Run the commit-msg hook without modifying the head commit by writing
         # the commit message to a temporary file and running the hook over it,
         # then reading the file back in.
         commit_msg_hook = os.path.join(settings.GetRoot(), '.git', 'hooks',
                                        'commit-msg')
         file_handle, msg_file = tempfile.mkstemp(text=True,
                                                  prefix='commit_msg')
+        logging.debug("%s %s", file_handle, msg_file)
         try:
           try:
-            with os.fdopen(file_handle, 'w') as fileobj:
+            try:
+              fileobj = os.fdopen(file_handle, 'w')
+            except OSError:
+              # if fdopen fails, file_handle remains open.
+              # See https://docs.python.org/2/library/os.html#os.fdopen.
+              os.close(file_handle)
+              raise
+            with fileobj:
+              # This will close the file_handle.
               fileobj.write(change_desc.description)
+            logging.debug("%s %s finish editing", file_handle, msg_file)
           finally:
-            os.close(file_handle)
             RunCommand([commit_msg_hook, msg_file])
             change_desc.set_description(gclient_utils.FileRead(msg_file))
         finally:
           os.remove(msg_file)
 
       if not change_desc.description:
         print "Description is empty; aborting."
         return 1
 
       message = change_desc.description
@@ skipping 1666 matching lines @@
 if __name__ == '__main__':
   # These affect sys.stdout so do it outside of main() to simplify mocks in
   # unit testing.
   fix_encoding.fix_encoding()
   colorama.init()
   try:
     sys.exit(main(sys.argv[1:]))
   except KeyboardInterrupt:
     sys.stderr.write('interrupted\n')
     sys.exit(1)