[Findit] Move configurable parameters in try_job_util.py to config

appengine/findit/handlers/config.py

Index: appengine/findit/handlers/config.py
diff --git a/appengine/findit/handlers/config.py b/appengine/findit/handlers/config.py
index c9e0e03129d37bc98ce835339d148ba8f6a73e34..130550bfd9063ffa419591fe9ef2c49378bea3eb 100644
--- a/appengine/findit/handlers/config.py
+++ b/appengine/findit/handlers/config.py
@@ -151,7 +151,8 @@ def _ValidateTryJobSettings(settings):
   return (isinstance(settings, dict) and
           isinstance(settings.get('server_query_interval_seconds'), int) and
           isinstance(settings.get('job_timeout_hours'), int) and
-          isinstance(settings.get('allowed_response_error_times'), int))
+          isinstance(settings.get('allowed_response_error_times'), int) and
+          isinstance(settings.get('max_seconds_look_back_for_group'), int))
 
 
 def _ValidateSwarmingSettings(settings):