[Security] Make saving target_path extendible

src/Symfony/Component/Security/Http/Firewall/ExceptionListener.php

@@ -157,11 +157,16 @@ class ExceptionListener
             $this->logger->debug('Calling Authentication entry point');
         }
 
+        $this->setTargetPath($request);
+
+        return $this->authenticationEntryPoint->start($request, $authException);
+    }
+
+    protected function setTargetPath(Request $request)
+    {
         // session isn't required when using http basic authentication mechanism for example
         if ($request->hasSession()) {
             $request->getSession()->set('_security.target_path', $request->getUri());
         }
-
-        return $this->authenticationEntryPoint->start($request, $authException);
     }
 }