sonata-project/SonataDoctrineORMAdminBundle — pull request #340 by kluevandrew (2014-04-08 06:55:57+00:00)
Title: Fix error in many to one template

Sometimes we got something like this Proxies\__CG__\Acme\AdminBundle\Entity\Sample with id == null as value, if we try to generate url for this object, we got excpetion with message:
```
"Parameter "id" for route "admin_acme_admin_sample_edit" must match "[^/]++" ("" given)
to generate a corresponding URL."
```
I fixed this bug.

PS:
I got this error then create list like:
``` php
protected function configureListFields(ListMapper $list)
{
$list->add('city.country');
$list->add('city');
$list->addIdentifier('name');

parent::configureListFields($list);
}
```