GTTF: make gclient config overwrite the .gclient file if it exists

gclient.py

 #!/usr/bin/env python
 # 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.
 
 """Meta checkout manager supporting both Subversion and GIT.
 
 Files
   .gclient      : Current client configuration, written by 'config' command.
                   Format is a Python script defining 'solutions', a list whose
@@ skipping 963 matching lines @@
   parser.add_option('--deps-file', default='DEPS',
                     help='overrides the default name for the DEPS file for the'
                          'main solutions and all sub-dependencies')
   parser.add_option('--git-deps', action='store_true',
                     help='sets the deps file to ".DEPS.git" instead of "DEPS"')
   (options, args) = parser.parse_args(args)
   if ((options.spec and args) or len(args) > 2 or
       (not options.spec and not args)):
     parser.error('Inconsistent arguments. Use either --spec or one or 2 args')
 
-  if os.path.exists(options.config_filename):
-    raise gclient_utils.Error('%s file already exists in the current directory'
-                                  % options.config_filename)
   client = GClient('.', options)
   if options.spec:
     client.SetConfig(options.spec)
   else:
     base_url = args[0].rstrip('/')
     if not options.name:
       name = base_url.split('/')[-1]
       if name.endswith('.git'):
         name = name[:-4]
     else:
@@ skipping 308 matching lines @@
   except (gclient_utils.Error, subprocess2.CalledProcessError), e:
     print >> sys.stderr, 'Error: %s' % str(e)
     return 1
 
 
 if '__main__' == __name__:
   fix_encoding.fix_encoding()
   sys.exit(Main(sys.argv[1:]))
 
 # vim: ts=2:sw=2:tw=80:et: