Catch IOError instead of OSError

tools/dom/scripts/multiemitter.py

 #!/usr/bin/python
 # Copyright (c) 2011, the Dart project authors.  Please see the AUTHORS file
 # for details. All rights reserved. Use of this source code is governed by a
 # BSD-style license that can be found in the LICENSE file.
 
 """Templating to help generate structured text."""
 
 import os
 import re
 import sys
@@ skipping 70 matching lines @@
   if os.path.exists(path):
     _logger.info('Removing - %s' % path)
     os.remove(path)
 
   # Write the file.
   try:
     _logger.info('Writing - %s' % path)
     f = open(path, 'w')
     f.writelines(lines)
     f.close()
-  except OSError as error:
+  except IOError as error:
     # FIXME(kustermann): Remove this later on.
     # We try to get more debugging information to figure out why we sometimes
     # get a "Permission denied" error when opening the file for writing.
     # (hypothesis: Another process has already opened the file.)
     _logger.info('Got exception (%s) ' % error)
 
     if sys.platform  == 'win32':
       handle_file = r'E:\handle.exe'
       if os.path.exists(handle_file):
         _logger.info('Running handle.exe for debugging purposes')
         subprocess.call([handle_file])
       else:
         _logger.info("Couldn't find %s. Not printing open handles."
                      % handle_file)
     raise error