fixed TPersistent process in TJSONWriter.WriteObject
- thanks Jordi for the pull request in
Merge commit 'fd3b4e01c206d99f299571dc21a346ab22ccb7e6'

* commit 'fd3b4e01c206d99f299571dc21a346ab22ccb7e6':
  fixed TPersistent process in TJSONWriter.WriteObject - thanks Jordi for the pull request in