fix the problem with history tables as table children (#335)

src/Microsoft.SqlTools.ServiceLayer/ObjectExplorer/SmoModel/SmoQuerier.cs

@@ -65,6 +65,14 @@ namespace Microsoft.SqlTools.ServiceLayer.ObjectExplorer.SmoModel
             return reader;
         }
 
+        /// <summary>
+        /// Mthod used to do custom filtering on smo objects if cannot be implemented using the filters
+        /// </summary>
+        protected virtual bool PassesFinalFilters(SqlSmoObject parent, SqlSmoObject smoObject)
+        {
+            return true;
+        }
+
         /// <summary>
         /// Gets the urn from the enumResult 
         /// </summary>