[Serializer] Abstract classes now implement their respective interfaces

src/Symfony/Component/Serializer/Encoder/AbstractEncoder.php

@@ -18,7 +18,7 @@ use Symfony\Component\Serializer\SerializerInterface;
  *
  * @author Jordi Boggiano <j.boggiano@seld.be>
  */
-abstract class AbstractEncoder
+abstract class AbstractEncoder implements EncoderInterface
 {
     protected $serializer;
 

src/Symfony/Component/Serializer/Encoder/JsonEncoder.php

@@ -18,7 +18,7 @@ use Symfony\Component\Serializer\SerializerInterface;
  *
  * @author Jordi Boggiano <j.boggiano@seld.be>
  */
-class JsonEncoder extends AbstractEncoder implements EncoderInterface
+class JsonEncoder extends AbstractEncoder
 {
     /**
      * {@inheritdoc}

src/Symfony/Component/Serializer/Encoder/XmlEncoder.php

@@ -20,7 +20,7 @@ use Symfony\Component\Serializer\SerializerInterface;
  * @author John Wards <jwards@whiteoctober.co.uk>
  * @author Fabian Vogler <fabian@equivalence.ch>
  */
-class XmlEncoder extends AbstractEncoder implements EncoderInterface
+class XmlEncoder extends AbstractEncoder
 {
     protected $dom;
     protected $format;

src/Symfony/Component/Serializer/Normalizer/AbstractNormalizer.php

@@ -18,7 +18,7 @@ use Symfony\Component\Serializer\SerializerInterface;
  *
  * @author Jordi Boggiano <j.boggiano@seld.be>
  */
-abstract class AbstractNormalizer
+abstract class AbstractNormalizer implements NormalizerInterface
 {
     protected $serializer;
 

src/Symfony/Component/Serializer/Normalizer/CustomNormalizer.php

@@ -16,7 +16,7 @@ use Symfony\Component\Serializer\SerializerInterface;
 /**
  * @author Jordi Boggiano <j.boggiano@seld.be>
  */
-class CustomNormalizer extends AbstractNormalizer implements NormalizerInterface
+class CustomNormalizer extends AbstractNormalizer
 {
     /**
      * {@inheritdoc}

src/Symfony/Component/Serializer/Normalizer/GetSetMethodNormalizer.php

@@ -33,7 +33,7 @@ use Symfony\Component\Serializer\SerializerInterface;
  *
  * @author Nils Adermann <naderman@naderman.de>
  */
-class GetSetMethodNormalizer extends AbstractNormalizer implements NormalizerInterface
+class GetSetMethodNormalizer extends AbstractNormalizer
 {
     /**
      * {@inheritdoc}