SkipyEmptyValues doesn't serialize correctly null object property value

[bobprog72]

testskip.zip

Model

type
TChildObject = class
private
FchildProp: string;
public
property childProp: string read FchildProp write FchildProp;
end;

type
TMainObject = class
private
FmainProp: string;
Fchild: TChildObject;
public
property mainProp: string read FmainProp write FmainProp;
property child: TChildObject read Fchild write FChild; <<<------------
end;

---

IMPLEMENTATION

function TTestResource.Test: string;
begin
var LMain := TMainObject.Create;
LMain.mainProp := 'mainProp';

var LJO := TJSONObject.Create;
try
LJO.FromObject( LMain );

ForceDirectories( 'c:\tteemmpp' );
TFile.WriteAllText( 'c:\tteemmpp\xxx.json', LJO.ToJSON );

finally
LJO.Free;
LMain.Free;
end;
end;

---

RESULT (xxx.json)

{"mainProp":"mainProp","child":null}

The "child" property appears with null value. I think that with SkipEmptyValues=true the property must not exist.