Extract authentication options handling into a separate function.

gcl.py

Index: gcl.py
diff --git a/gcl.py b/gcl.py
index cf657893c737133e5266ad8ff27bb052295f2ee0..32cbbf7e58c69ebdedcb850d5da095b5af039fb5 100755
--- a/gcl.py
+++ b/gcl.py
@@ -23,6 +23,7 @@ import urllib2
 import breakpad  # pylint: disable=W0611
 
 
+import auth
 import fix_encoding
 import gclient_utils
 import git_cl
@@ -351,7 +352,10 @@ class ChangeInfo(object):
     if not self._rpc_server:
       if not self.rietveld:
         ErrorExit(CODEREVIEW_SETTINGS_FILE_NOT_FOUND)
-      self._rpc_server = rietveld.CachingRietveld(self.rietveld, None, None)
+      # TODO(vadimsh): glc.py should be deleted soon. Do not bother much about
+      # authentication options and always use defaults.
+      self._rpc_server = rietveld.CachingRietveld(
+          self.rietveld, auth.make_auth_config())
     return self._rpc_server
 
   def CloseIssue(self):