Issue #2310527 by damiankloip: Upgrade Serializer component to 2.5.2.

core/vendor/composer/ClassLoader.php

core/vendor/composer/installed.json

...fony/serializer/Symfony/Component/Serializer/CHANGELOG.md

...zer/Symfony/Component/Serializer/Encoder/ChainEncoder.php

...Symfony/Component/Serializer/Encoder/DecoderInterface.php

...Symfony/Component/Serializer/Encoder/EncoderInterface.php

...lizer/Symfony/Component/Serializer/Encoder/JsonDecode.php

...lizer/Symfony/Component/Serializer/Encoder/JsonEncode.php

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

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

...r/symfony/serializer/Symfony/Component/Serializer/LICENSE

...fony/Component/Serializer/Normalizer/CustomNormalizer.php

...Component/Serializer/Normalizer/DenormalizerInterface.php

...omponent/Serializer/Normalizer/GetSetMethodNormalizer.php

...y/Component/Serializer/Normalizer/NormalizerInterface.php

...ny/serializer/Symfony/Component/Serializer/Serializer.php

...ny/Component/Serializer/Tests/Encoder/JsonEncoderTest.php

...ony/Component/Serializer/Tests/Encoder/XmlEncoderTest.php

...nent/Serializer/Tests/Normalizer/CustomNormalizerTest.php

...erializer/Tests/Normalizer/GetSetMethodNormalizerTest.php