Automatically fill in necessary properties for retention on metadata

As a developer using nuxeo studio designer, I want to have configuration that allows to use retention on metadata capabilities with minimal effort

Context
Since WEBUI-989, for the elements to check if the property is retained or not
nuxeo-file exposes new properties (document and xpath)
nuxeo-dropzone requires the xpath property to be filled in

These properties are not filled in for the existing configuration (NXDOC-xx will explain this). The goal is to ensure that this change is taken into account for new configuration produced.

AC
When drag and dropping a property from the catalog and using of the elements below, the following properties and values are added on top of the existing:

• • nuxeo-file document: default value for document (

    {{document}}

    ? nsingh@ext.nuxeo.com and dev team to check and update if needed)

  • nuxeo-file xpath: xpath of the property being drag and dropped
  • nuxeo-dropzone xpath: xpath of the property being drag and dropped

When drag and dropping the element directly from the catalog:

• these properties are added inside the code on top of the existing with the following values:
  • nuxeo-file document: default value for document (

    {{document}}

    ? nsingh@ext.nuxeo.com and dev team to check and update if needed)

  • nuxeo-file xpath: empty value
  • nuxeo-dropzone xpath: empty value