Resourcetype settings for "contains Objects" in tinymce controlpanel are not respected for folderish custom dexterity types

[fgrcon]

In a tinymce textarea one can not select contents of such a folderish type relates to: plone 5.0rc2 / current coredev

Steps to reproduce

• create a folderish dexterity type (eg: copy Folder to Folder1) (either ttw or by an addon product)
• add type to tinymce settings
• add an instance folder1-1 of this type to your site
• add some new items to folder1-1 (images, pages)
• create a testpage some where on the site
• try to insert an image via tinymce: folder1-1 is not found.... or try to create a link .. folder1-1 can not be expanded

[pbauer]

The setting is correctly picked up by plone.app.widgets.utils.get_tinymce_options from the tinymce-controlpanel but aparently not respected in the pattern itself.