AMBARI-12951. Prompt user to save checkpoint before shutdown if last checkpoint is too old. (xiwang via yusaku)

ambari-web/app/controllers/main/service/item.js

@@ -260,7 +260,7 @@ App.MainServiceItemController = Em.Controller.extend(App.SupportClientConfigsDow
     if (!lastCheckpointTime) {
       this.set("isNNCheckpointTooOld", null);
     } else {
-      var time_criteria = 12; // time in hours to define how many hours ago is too old
+      var time_criteria = App.nnCheckpointAgeAlertThreshold; // time in hours to define how many hours ago is too old
       var time_ago = (Math.round(App.dateTime() / 1000) - (time_criteria * 3600)) *1000;
       if (lastCheckpointTime <= time_ago) {
         // too old, set the effected hostName