[Findit] Factoring the gitiles (etc) stuff out into its own directory

appengine/findit/common/rietveld.py

 # Copyright 2016 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.
 
+# TODO: In the new layout, this should move to the ./services or
+# ./services/waterfall_app directories, since it is only used by Waterfall.
+
+# TODO: we ought to abstract over the HTTP_CLIENT member (which is only
+# used by the Post method) by passing it to the constructor. That way
+# things are more losely coupled, improving modularity and reducing
+# fragility. In addition, for easier mocking, we may want to just have
+# the thing passed for HTTP_CLIENT to be ``callable``, rather than giving
+# a name to the method we use on that object.
+
 import logging
 import re
 import urlparse
 
-from common.codereview import CodeReview
 from common.http_client_appengine import HttpClientAppengine
 
 
 _RIETVELD_ISSUE_NUMBER_RE = re.compile('^/(\d+)/?.*')
 
 
-class Rietveld(CodeReview):
+class Rietveld(object):
   """The implementation of CodeReview interface for Rietveld."""
   HTTP_CLIENT = HttpClientAppengine(follow_redirects=False)
 
   def _GetXsrfToken(self, rietveld_url):
     """Returns the xsrf token for follow-up requests."""
     headers = {
         'X-Requesting-XSRF-Token': '1',
         'Accept': 'text/plain',
     }
     url = '%s/xsrf_token' % rietveld_url
@@ skipping 50 matching lines @@
         'no_redirect': 'True',
     }
     content_type, body = self._EncodeMultipartFormData(form_fields)
     headers = {
         'Content-Type': content_type,
         'Accept': 'text/plain',
     }
     status_code, content = self.HTTP_CLIENT.Post(
         url, data=body, headers=headers)
     return status_code == 200 and content == 'OK'