feature #18036 [Serializer] XmlEncoder: Make load flags configurable …

…(dunglas)

This PR was squashed before being merged into the 3.1-dev branch (closes #18036).

Discussion
----------

[Serializer] XmlEncoder: Make load flags configurable

| Q             | A
| ------------- | ---
| Branch        | master
| Bug fix?      | no
| New feature?  | yes
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | #17987
| License       | MIT
| Doc PR        | todo

Commits
-------

0826068 [Serializer] XmlEncoder: Make load flags configurable

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

@@ -30,15 +30,18 @@ class XmlEncoder extends SerializerAwareEncoder implements EncoderInterface, Dec
     private $format;
     private $context;
     private $rootNodeName = 'response';
+    private $loadOptions;
 
     /**
      * Construct new XmlEncoder and allow to change the root node element name.
      *
-     * @param string $rootNodeName
+     * @param string   $rootNodeName
+     * @param int|null $loadOptions  A bit field of LIBXML_* constants
      */
-    public function __construct($rootNodeName = 'response')
+    public function __construct($rootNodeName = 'response', $loadOptions = null)
     {
         $this->rootNodeName = $rootNodeName;
+        $this->loadOptions = null !== $loadOptions ? $loadOptions : LIBXML_NONET | LIBXML_NOBLANKS;
     }
 
     /**
@@ -81,7 +84,7 @@ public function decode($data, $format, array $context = array())
         libxml_clear_errors();
 
         $dom = new \DOMDocument();
-        $dom->loadXML($data, LIBXML_NONET | LIBXML_NOBLANKS);
+        $dom->loadXML($data, $this->loadOptions);
 
         libxml_use_internal_errors($internalErrors);
         libxml_disable_entity_loader($disableEntities);