[FrameworkBundle] Updated kernel test to create tmp directory on instantiation

src/Symfony/Bundle/FrameworkBundle/Tests/Kernel.php

@@ -20,6 +20,13 @@ class Kernel extends BaseKernel
     public function __construct()
     {
         $this->tmpDir = sys_get_temp_dir().'/sf2_'.rand(1, 9999);
+        if (!is_dir($this->tmpDir)) {
+            if (false === @mkdir($this->tmpDir)) {
+                die(sprintf('Unable to create a temporary directory (%s)', $this->tmpDir));
+            }
+        } elseif (!is_writable($this->tmpDir)) {
+            die(sprintf('Unable to write in a temporary directory (%s)', $this->tmpDir));
+        }
 
         parent::__construct('env', true);
     }