minor #6939 Fixed Request Factory Example (vdambeck)

This PR was submitted for the master branch but it was merged into the 2.7 branch instead (closes #6939).

Discussion
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Fixed Request Factory Example

The Request Factory Example dosen't work anymore.
I change the example code. So it will work now.

Commits
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c877fce change request factory example code

Author: xabbuh

components/http_foundation.rst

@@ -293,6 +293,7 @@ methods or changing some default behavior might help. In that case, register a
 PHP callable that is able to create an instance of your ``Request`` class::
 
     use Symfony\Component\HttpFoundation\Request;
+    use AppBundle\Classes\SpecialRequest;
 
     Request::setFactory(function (
         array $query = array(),
@@ -303,7 +304,7 @@ PHP callable that is able to create an instance of your ``Request`` class::
         array $server = array(),
         $content = null
     ) {
-        return SpecialRequest::create(
+        return new SpecialRequest(
             $query,
             $request,
             $attributes,