Add repository root presubmit support.

gcl.py

 #!/usr/bin/python
 # Copyright (c) 2006-2009 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.
 #
 # Wrapper script around Rietveld's upload.py that groups files into
 # changelists.
 
 import getpass
 import os
@@ skipping 589 matching lines @@
 Basic commands:
 -----------------------------------------
    gcl change change_name
       Add/remove files to a changelist. Only scans the current directory and
       subdirectories.
 
    gcl upload change_name [-r reviewer1@gmail.com,reviewer2@gmail.com,...]
                           [--send_mail] [--no_try] [--no_presubmit]
       Uploads the changelist to the server for review.
 
-   gcl commit change_name [--force]
+   gcl commit change_name [--no_presubmit] [--force]
       Commits the changelist to the repository.
 
    gcl lint change_name
       Check all the files in the changelist for possible style violations.
 
 Advanced commands:
 -----------------------------------------
    gcl delete change_name
       Deletes a changelist.
 
@@ skipping 395 matching lines @@
         cpplint.ProcessFile(file, cpplint._cpplint_state.verbose_level)
 
   print "Total errors found: %d\n" % cpplint._cpplint_state.error_count
   os.chdir(previous_cwd)
 
 
 def DoPresubmitChecks(change_info, committing):
   """Imports presubmit, then calls presubmit.DoPresubmitChecks."""
   # Need to import here to avoid circular dependency.
   import presubmit_support
+  root_presubmit = GetCachedFile('PRESUBMIT.py', use_root=True)
   result = presubmit_support.DoPresubmitChecks(change_info,
                                                committing,
                                                verbose=False,
                                                output_stream=sys.stdout,
-                                               input_stream=sys.stdin)
+                                               input_stream=sys.stdin,
+                                               default_presubmit=root_presubmit)
   if not result:
     print "\nPresubmit errors, can't continue (use --no_presubmit to bypass)"
   return result
 
 
 def Changes():
   """Print all the changelists and their files."""
   for cl in GetCLs():
     change_info = LoadChangelistInfo(cl, True, True)
     print "\n--- Changelist " + change_info.name + ":"
@@ skipping 97 matching lines @@
     # the files. This allows commands such as 'gcl diff xxx' to work.
     args =["svn", command]
     root = GetRepositoryRoot()
     args.extend([os.path.join(root, x) for x in change_info.FileList()])
     RunShell(args, True)
   return 0
 
 
 if __name__ == "__main__":
   sys.exit(main())