Conversion of NAIndicatorTransform to estimator with related pigstensions

src/Microsoft.ML.Transforms/NAHandleTransform.cs

@@ -212,7 +212,7 @@ public static IDataTransform Create(IHostEnvironment env, Arguments args, IDataV
 
             // Create the indicator columns.
             if (naIndicatorCols.Count > 0)
-                output = new NAIndicatorTransform(h, new NAIndicatorTransform.Arguments() { Column = naIndicatorCols.ToArray() }, input);
+                output = NAIndicatorTransform.Create(h, new NAIndicatorTransform.Arguments() { Column = naIndicatorCols.ToArray() }, input);
 
             // Convert the indicator columns to the correct type so that they can be concatenated to the NAReplace outputs.
             if (naConvCols.Count > 0)

src/Microsoft.ML.Transforms/NAHandling.cs

@@ -71,7 +71,7 @@ public static CommonOutputs.TransformOutput Handle(IHostEnvironment env, NAHandl
         public static CommonOutputs.TransformOutput Indicator(IHostEnvironment env, NAIndicatorTransform.Arguments input)
         {
             var h = EntryPointUtils.CheckArgsAndCreateHost(env, "NAIndicator", input);
-            var xf = new NAIndicatorTransform(h, input, input.Data);
+            var xf = NAIndicatorTransform.Create(h, input, input.Data);
             return new CommonOutputs.TransformOutput()
             {
                 Model = new TransformModel(h, xf, input.Data),