Exception occurs after sending item from Relation List to Trash.
- Create a Content Item from a Content Type with the ezobjectrelationlist field type.
- Add a valid item to the Relation List.
- Send the item from step 2 to Trash.
- Go to the item from step 1 in View mode.
Actual: Error 500 occurs, "Call to a member function getContent() on null [in vendor/ezsystems/ezplatform-admin-ui/src/lib/Specification/Location/IsContainer.php:22]".
Remarks: Affects also the ezobjectrelation (single) field type.