Update fetch to support more flexible refspecs

recipes/blink.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 json
 import sys
 
 import recipe_util  # pylint: disable=F0401
 
 
 # This class doesn't need an __init__ method, so we disable the warning
 # pylint: disable=W0232
 class Blink(recipe_util.Recipe):
   """Basic Recipe alias for Blink -> Chromium."""
 
   @staticmethod
   def fetch_spec(props):
     submodule_spec = {
       'third_party/WebKit': {
-        'svn_url': 'svn://svn.chromium.org/blink/trunk',

[Michael Achenbach, 2014/10/22 09:46:28]

So, auto-svn has a mapping from git to svn urls?

[agable, 2014/10/22 10:03:33]

auto-svn determines the mapping directly from the git-svn-id footer. That's why
it's "auto": no need for any configuration stored anywhere.

-        'svn_branch': 'trunk',
-        'svn_ref': 'master',
+        'auto': True,
       }
     }
     return {
       'alias': {
         'recipe': 'chromium',
         'props': [
           '--webkit_revision=ToT',
           '--submodule_git_svn_spec=' + json.dumps(submodule_spec),
         ],
       },
     }
 
 
 def main(argv=None):
   return Blink().handle_args(argv)
 
 
 if __name__ == '__main__':
   sys.exit(main(sys.argv))