Merge branch '2.5' into 2.6

* 2.5:
  fix dependency on ExtensionInterface over implementation
  [FrameworkBundle] forward error reporting level to insulated Client
  [Config] fix error handler restoration in test

Author: fabpot

Client.php

@@ -102,10 +102,13 @@ protected function getScript($request)
         $r = new \ReflectionClass('\\Symfony\\Component\\ClassLoader\\ClassLoader');
         $requirePath = str_replace("'", "\\'", $r->getFileName());
         $symfonyPath = str_replace("'", "\\'", realpath(__DIR__.'/../../..'));
+        $errorReporting = error_reporting();
 
         $code = <<<EOF
 <?php
 
+error_reporting($errorReporting);
+
 require_once '$requirePath';
 
 \$loader = new Symfony\Component\ClassLoader\ClassLoader();