Update fetch to support more flexible refspecs

recipes/chromium.py

 # Copyright (c) 2013 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.
 
 import sys
 
 import recipe_util  # pylint: disable=F0401
 
 
 # This class doesn't need an __init__ method, so we disable the warning
@@ skipping 13 matching lines @@
     }
     if props.get('webkit_revision', '') == 'ToT':
       solution['custom_vars'] = {'webkit_revision': ''}
     spec = {
       'solutions': [solution],
     }
     if props.get('target_os'):
       spec['target_os'] = props['target_os'].split(',')
     if props.get('target_os_only'):
       spec['target_os_only'] = props['target_os_only']
-    checkout_type = 'gclient_git'
-    spec_type = '%s_spec' % checkout_type
     return {
-      'type': checkout_type,
-      spec_type: spec,
+      'type': 'gclient_git',
+      'gclient_git_spec': spec,
     }
 
   @staticmethod
   def expected_root(_props):
     return 'src'
 
 
 def main(argv=None):
   return Chromium().handle_args(argv)
 
 
 if __name__ == '__main__':
   sys.exit(main(sys.argv))