[Findit] Extending versioned_model.py to support versioning multiple entities of the same class.

appengine/findit/waterfall/process_base_swarming_task_result_pipeline.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.
 
 from collections import defaultdict
 import datetime
 import logging
 import time
 
 from common.http_client_appengine import HttpClientAppengine as HttpClient
@@ skipping 112 matching lines @@
           task.status = analysis_status.RUNNING
           task.put()
         time.sleep(server_query_interval_seconds)
       if time.time() > deadline:
         # Updates status as ERROR.
         task = self._GetSwarmingTask(*call_args)
         task.status = analysis_status.ERROR
         task.put()
         logging.error('Swarming task timed out after %d hours.' % timeout_hours)
         break  # Stops the loop and return.
-    # Update swarming task metadate.
+    # Update swarming task metadata.
     task = self._GetSwarmingTask(*call_args)
     task.created_time = self._ConvertDateTime(data.get('created_ts'))
     task.started_time = self._ConvertDateTime(data.get('started_ts'))
     task.completed_time = self._ConvertDateTime(data.get('completed_ts'))
     task.put()
 
     return step_name, step_name_no_platform