bug #3869 Add a missing argument to the PdoSessionHandler (jakzal)

This PR was merged into the 2.3 branch.

Discussion
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Add a missing argument to the PdoSessionHandler

| Q	| A
| --- | ---
| Doc fix?	| yes
| New docs? |	no
| Applies to |	all
| Fixed tickets | #3868

Commits
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fff25ce Add a missing argument to the PdoSessionHandler.

components/http_foundation/session_configuration.rst

@@ -83,7 +83,8 @@ Example usage::
     use Symfony\Component\HttpFoundation\Session\Storage\NativeSessionStorage;
     use Symfony\Component\HttpFoundation\Session\Storage\Handler\PdoSessionHandler;
 
-    $storage = new NativeSessionStorage(array(), new PdoSessionHandler());
+    $pdo = new \PDO('mysql:dbname=testdb;host=127.0.0.1');
+    $storage = new NativeSessionStorage(array(), new PdoSessionHandler($pdo));
     $session = new Session($storage);
 
 Configuring PHP Sessions