feature #13885 [Serializer] Adds FormErrorNormalizer (YaFou)

This PR was merged into the master branch.

Discussion
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[Serializer] Adds FormErrorNormalizer

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This pull request is related to symfony/symfony#36211.

Commits
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9ed468d [Serializer] Adds FormErrorNormalizer

Author: wouterj

components/serializer.rst

@@ -796,6 +796,12 @@ There are several types of normalizers available:
     This normalizer converts :phpclass:`DateInterval` objects into strings.
     By default, it uses the ``P%yY%mM%dDT%hH%iM%sS`` format.
 
+:class:`Symfony\\Component\\Serializer\\Normalizer\\FormErrorNormalizer`
+    This normalizer works with classes that implement
+    :class:`Symfony\\Component\\Form\\FormInterface`.
+
+    It will get errors from the form and normalize them into an normalized array.
+
 :class:`Symfony\\Component\\Serializer\\Normalizer\\ConstraintViolationListNormalizer`
     This normalizer converts objects that implement
     :class:`Symfony\\Component\\Validator\\ConstraintViolationListInterface`

serializer.rst

@@ -67,6 +67,9 @@ As well as the following normalizers:
   for :phpclass:`DateInterval` objects
 * :class:`Symfony\\Component\\Serializer\\Normalizer\\DataUriNormalizer` to
   transform :phpclass:`SplFileInfo` objects in `Data URIs`_
+* :class:`Symfony\\Component\\Serializer\\Normalizer\\FormErrorNormalizer` for
+  objects implementing the :class:`Symfony\\Component\\Form\\FormInterface` to
+  normalize form errors.
 * :class:`Symfony\\Component\\Serializer\\Normalizer\\JsonSerializableNormalizer`
   to deal with objects implementing the :phpclass:`JsonSerializable` interface
 * :class:`Symfony\\Component\\Serializer\\Normalizer\\ArrayDenormalizer` to

serializer/normalizers.rst

@@ -36,6 +36,9 @@ Symfony includes the following normalizers but you can also
   transform :phpclass:`SplFileInfo` objects in `Data URIs`_
 * :class:`Symfony\\Component\\Serializer\\Normalizer\\CustomNormalizer` to
   normalize PHP object using an object that implements
+* :class:`Symfony\\Component\\Serializer\\Normalizer\\FormErrorNormalizer` for
+  objects implementing the :class:`Symfony\\Component\\Form\\FormInterface` to
+  normalize form errors.
   :class:`Symfony\\Component\\Serializer\\Normalizer\\NormalizableInterface`;
 * :class:`Symfony\\Component\\Serializer\\Normalizer\\GetSetMethodNormalizer` to
   normalize PHP object using the getter and setter methods of the object;