Ensuring that a new url is used after refreshing the credentials.

apitools/base/py/credentials_lib.py

@@ -570,18 +570,23 @@ def GetUserinfo(credentials, http=None):  # pylint: disable=invalid-name
       aren't available.
     """
     http = http or httplib2.Http()
-    url_root = 'https://www.googleapis.com/oauth2/v2/tokeninfo'
-    query_args = {'access_token': credentials.access_token}
-    url = '?'.join((url_root, urllib.parse.urlencode(query_args)))
+    url = _GetUserinfoUrl(credentials)
     # We ignore communication woes here (i.e. SSL errors, socket
     # timeout), as handling these should be done in a common location.
     response, content = http.request(url)
     if response.status == http_client.BAD_REQUEST:
         credentials.refresh(http)
+        url = _GetUserinfoUrl(credentials)
         response, content = http.request(url)
     return json.loads(content or '{}')  # Save ourselves from an empty reply.
 
 
+def _GetUserinfoUrl(credentials):
+    url_root = 'https://www.googleapis.com/oauth2/v2/tokeninfo'
+    query_args = {'access_token': credentials.access_token}
+    return '?'.join((url_root, urllib.parse.urlencode(query_args)))
+
+
 @_RegisterCredentialsMethod
 def _GetServiceAccountCredentials(
         client_info, service_account_name=None, service_account_keyfile=None,