There is an unhandled exception thrown when accessing content having relation to another one being a part of restricted section.

Steps to reproduce:

1. Create a new "test" user.
2. Create a new section and name it "testSection".
3. Create a new article "allowed" and assign it to "testSection".
4. Create a new article "restricted" without any section assigned.
5. Edit "allowed" and add "restricted" article as a relation in the ezrelationlist FieldType.
6. Create a new role "testRole" with the following policies and limitations:

   Module	Function	Limitations
   Content	Read	Section: testSection
   Content	Reverserelatedlist	None
   Content	Create	None
   Content	Edit	Section: testSection
   Content	Publish	Section: testSection
   Content	Manage_locations	None
   User	*	None

7. Assign "testRole" to "test" user.
8. Login as "test".
9. Try to access "allowed" content.

Result:

You will be presented with an error, see stacktrace.png for further details.

An exception has been thrown during the rendering of a template ("User does not have access to 'read' 'content' with: contentId '56'") in "EzPlatformAdminUiBundle:fieldtypes/preview:content_fields.html.twig".

Note:
The issue is reproducible in dev environment.