[recipes.cfg] ONLY support jsonpb.

recipe_engine/fetch.py

 # Copyright 2016 The LUCI Authors. All rights reserved.
 # Use of this source code is governed under the Apache License, Version 2.0
 # that can be found in the LICENSE file.
 
 import base64
 import httplib
 import json
 import logging
 import os
 import re
 import shutil
 import sys
 import tarfile
 import tempfile
 
 # Add third party paths.
 from . import env
 from . import requests_ssl
 from . import util
 from . import types
 from .requests_ssl import requests
 
 import subprocess42
-from google.protobuf import text_format
+from google.protobuf import json_format
 
 from . import package_pb2
 
 
 class FetchError(Exception):
   pass
 
 
 class FetchNotAllowedError(FetchError):
   pass
@@ skipping 218 matching lines @@
 
     revision = self._resolve_revision(repo, revision)
 
     shutil.rmtree(checkout_dir, ignore_errors=True)
 
     recipes_cfg_url = '%s/+/%s/infra/config/recipes.cfg?format=TEXT' % (
         repo, requests.utils.quote(revision))
     recipes_cfg_text = base64.b64decode(
         self._fetch_gitiles(recipes_cfg_url).text)
     recipes_cfg_proto = package_pb2.Package()
-    text_format.Merge(recipes_cfg_text, recipes_cfg_proto)
+    json_format.Parse(recipes_cfg_text, recipes_cfg_proto,
+                      ignore_unknown_fields=True)
     recipes_path_rel = recipes_cfg_proto.recipes_path
 
     # Re-create recipes.cfg in |checkout_dir| so that the repo's recipes.py
     # can look it up.
     recipes_cfg_path = os.path.join(
         checkout_dir, 'infra', 'config', 'recipes.cfg')
     os.makedirs(os.path.dirname(recipes_cfg_path))
     with open(recipes_cfg_path, 'w') as f:
       f.write(recipes_cfg_text)
 
@@ skipping 84 matching lines @@
     logging.info('fetching %s', url)
 
     resp = requests.get(url)
     if resp.status_code != httplib.OK:
       raise GitilesFetchError(resp.status_code, resp.text)
 
     if not resp.text.startswith(cls._GERRIT_XSRF_HEADER):
       raise GitilesFetchError(resp.status_code, 'Missing XSRF header')
 
     return json.loads(resp.text[len(cls._GERRIT_XSRF_HEADER):])