minor #11394 edit normalizer deprecated method on 4.2 (Raulnet)

This PR was merged into the 4.2 branch.

Discussion
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edit normalizer deprecated method on 4.2

i have added documentation for deprecated method in Normalizer
`Symfony\Component\Serializer\Normalizer\AbstractNormalizer::setCallbacks`
`Symfony\Component\Serializer\Normalizer\AbstractNormalizer::setCircularReferenceLimit`
`Symfony\Component\Serializer\Normalizer\AbstractNormalizer::setMaxDepthHandler`

And edit the code for the new params declaration;
And move the text `..deprecated 4.2 ...` below the demo code for more consistency

Commits
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f02e6fd edit normalizer deprecated method on 4.2

Author: wouterj

components/serializer.rst

@@ -639,7 +639,7 @@ When serializing, you can set a callback to format a specific object property::
     $encoder = new JsonEncoder();
 
     // all callback parameters are optional (you can omit the ones you don't use)
-    $callback = function ($innerObject, $outerObject, string $attributeName, string $format = null, array $context = []) {
+    $dateCallback = function ($innerObject, $outerObject, string $attributeName, string $format = null, array $context = []) {
         return $innerObject instanceof \DateTime ? $innerObject->format(\DateTime::ISO8601) : '';
     };
 
@@ -661,6 +661,11 @@ When serializing, you can set a callback to format a specific object property::
     $serializer->serialize($person, 'json');
     // Output: {"name":"cordoval", "age": 34, "createdAt": "2014-03-22T09:43:12-0500"}
 
+.. deprecated:: 4.2
+
+    The :method:`Symfony\\Component\\Serializer\\Normalizer\\AbstractNormalizer::setCallbacks` is deprecated since
+    Symfony 4.2, use the "callbacks" key of the context instead.
+
 .. _component-serializer-normalizers:
 
 Normalizers
@@ -931,15 +936,9 @@ when such a case is encountered::
 
     echo $serializer->serialize($organization, 'json'); // Throws a CircularReferenceException
 
-The ``setCircularReferenceLimit()`` method of this normalizer sets the number
-of times it will serialize the same object before considering it a circular
-reference. Its default value is ``1``.
-
-.. deprecated:: 4.2
-
-    The :method:`Symfony\\Component\\Serializer\\Normalizer\\AbstractNormalizer::setCircularReferenceHandler`
-    method is deprecated since Symfony 4.2. Use the ``circular_reference_handler``
-    key of the context instead.
+The key ``circular_reference_limit`` in the default context sets the number of
+times it will serialize the same object before considering it a circular
+reference. The default value is ``1``.
 
 Instead of throwing an exception, circular references can also be handled
 by custom callables. This is especially useful when serializing entities
@@ -957,6 +956,12 @@ having unique identifiers::
     var_dump($serializer->serialize($org, 'json'));
     // {"name":"Les-Tilleuls.coop","members":[{"name":"K\u00e9vin", organization: "Les-Tilleuls.coop"}]}
 
+.. deprecated:: 4.2
+
+    The :method:`Symfony\\Component\\Serializer\\Normalizer\\AbstractNormalizer::setCircularReferenceHandler`
+    method is deprecated since Symfony 4.2. Use the ``circular_reference_handler``
+    key of the context instead.
+
 Handling Serialization Depth
 ----------------------------
 
@@ -1084,11 +1089,16 @@ having unique identifiers::
     $level2->child = $level3;
 
     $classMetadataFactory = new ClassMetadataFactory(new AnnotationLoader(new AnnotationReader()));
-    $normalizer = new ObjectNormalizer($classMetadataFactory);
+
     // all callback parameters are optional (you can omit the ones you don't use)
-    $normalizer->setMaxDepthHandler(function ($innerObject, $outerObject, string $attributeName, string $format = null, array $context = []) {
+    $maxDepthHandler = function ($innerObject, $outerObject, string $attributeName, string $format = null, array $context = []) {
         return '/foos/'.$innerObject->id;
-    });
+    };
+
+    $defaultContext = [
+        AbstractObjectNormalizer::MAX_DEPTH_HANDLER => $maxDepthHandler,
+    ];
+    $normalizer = new ObjectNormalizer($classMetadataFactory, null, null, null, null, null, $defaultContext);
 
     $serializer = new Serializer([$normalizer]);
 
@@ -1103,6 +1113,12 @@ having unique identifiers::
     ];
     */
 
+.. deprecated:: 4.2
+
+    The :method:`Symfony\\Component\\Serializer\\Normalizer\\AbstractNormalizer::setMaxDepthHandler`
+    method is deprecated since Symfony 4.2. Use the ``max_depth_handler``
+    key of the context instead.
+
 Handling Arrays
 ---------------