It is as I said in the PR description, but unless I specify that value, I get: 

```
20) FSC\HateoasBundle\Tests\Functional\Serializer\XmlFormViewSerializerTest::testAttributes
ErrorException: Notice: Undefined index: translation_domain in /Users/brensch/code/FSCHateoasBundle/vendor/symfony/framework-bundle/Symfony/Bundle/FrameworkBundle/DependencyInjection/FrameworkExtension.php line 603

/Users/brensch/code/FSCHateoasBundle/vendor/symfony/framework-bundle/Symfony/Bundle/FrameworkBundle/DependencyInjection/FrameworkExtension.php:603
/Users/brensch/code/FSCHateoasBundle/vendor/symfony/framework-bundle/Symfony/Bundle/FrameworkBundle/DependencyInjection/FrameworkExtension.php:90
/Users/brensch/code/FSCHateoasBundle/vendor/symfony/dependency-injection/Symfony/Component/DependencyInjection/Compiler/MergeExtensionConfigurationPass.php:50
/Users/brensch/code/FSCHateoasBundle/vendor/symfony/http-kernel/Symfony/Component/HttpKernel/DependencyInjection/MergeExtensionConfigurationPass.php:39
/Users/brensch/code/FSCHateoasBundle/vendor/symfony/dependency-injection/Symfony/Component/DependencyInjection/Compiler/Compiler.php:119
/Users/brensch/code/FSCHateoasBundle/vendor/symfony/dependency-injection/Symfony/Component/DependencyInjection/ContainerBuilder.php:553
/Users/brensch/code/FSCHateoasBundle/vendor/symfony/http-kernel/Symfony/Component/HttpKernel/Kernel.php:664
/Users/brensch/code/FSCHateoasBundle/vendor/symfony/http-kernel/Symfony/Component/HttpKernel/Kernel.php:556
/Users/brensch/code/FSCHateoasBundle/vendor/symfony/http-kernel/Symfony/Component/HttpKernel/Kernel.php:139
/Users/brensch/code/FSCHateoasBundle/Tests/Functional/TestCase.php:25
/Users/brensch/code/FSCHateoasBundle/Tests/Functional/TestCase.php:30
/Users/brensch/code/FSCHateoasBundle/Tests/Functional/Serializer/XmlFormViewSerializerTest.php:358
```