Revert "Fix non-existent MFA cluster property caused NPE issue"

This reverts commit 46d6a16

Author: wezhang

Utils/hdinsight-node-common/src/com/microsoft/azure/hdinsight/common/ClusterManagerEx.java

@@ -412,11 +412,10 @@ List<IClusterDetail> loadAdditionalClusters() {
 
         isListAdditionalClusterSuccess = false;
         Gson gson = new Gson();
-        final String DEFAULT_EMPTY_JSON = "[]";
-        String additionalClustersJson = DefaultLoader.getIdeHelper().getPropertyWithDefault(CommonConst.HDINSIGHT_ADDITIONAL_CLUSTERS, DEFAULT_EMPTY_JSON);
-        String additionalMfaClustersJson = DefaultLoader.getIdeHelper().getPropertyWithDefault(CommonConst.HDINSIGHT_ADDITIONAL_MFA_CLUSTERS, DEFAULT_EMPTY_JSON);
-        String livyLinkClustersJson = DefaultLoader.getIdeHelper().getPropertyWithDefault(CommonConst.HDINSIGHT_LIVY_LINK_CLUSTERS, DEFAULT_EMPTY_JSON);
-        String sqlBigDataClustersJson = DefaultLoader.getIdeHelper().getPropertyWithDefault(CommonConst.SQL_BIG_DATA_LIVY_LINK_CLUSTERS, DEFAULT_EMPTY_JSON);
+        String additionalClustersJson = DefaultLoader.getIdeHelper().getApplicationProperty(CommonConst.HDINSIGHT_ADDITIONAL_CLUSTERS);
+        String additionalMfaClustersJson = DefaultLoader.getIdeHelper().getApplicationProperty(CommonConst.HDINSIGHT_ADDITIONAL_MFA_CLUSTERS);
+        String livyLinkClustersJson = DefaultLoader.getIdeHelper().getApplicationProperty(CommonConst.HDINSIGHT_LIVY_LINK_CLUSTERS);
+        String sqlBigDataClustersJson = DefaultLoader.getIdeHelper().getApplicationProperty(CommonConst.SQL_BIG_DATA_LIVY_LINK_CLUSTERS);
         if (!StringHelper.isNullOrWhiteSpace(additionalClustersJson) && !StringHelper.isNullOrWhiteSpace(livyLinkClustersJson)) {
             try {
                 hdiAdditionalClusters = gson.fromJson(additionalClustersJson, new TypeToken<ArrayList<HDInsightAdditionalClusterDetail>>() {