[HttpKernel] Dont close the output stream in debug

Author: nicolas-grekas

Response.php

@@ -373,12 +373,6 @@ public function send()
         $this->sendHeaders();
         $this->sendContent();
 
-        if (function_exists('fastcgi_finish_request')) {
-            fastcgi_finish_request();
-        } elseif ('cli' !== PHP_SAPI) {
-            static::closeOutputBuffers(0, true);
-        }
-
         return $this;
     }