[HttpKernel] Fix call to Memcached::set() in MemcachedProfilerStorage

The existing code seems to have been copied from MemcacheProfilerStorage. Memcache::set() includes a $flag argument, but Memcached::set() omits that. See:

 * http://php.net/manual/en/memcached.set.php
 * http://php.net/manual/en/memcache.set.php

src/Symfony/Component/HttpKernel/Profiler/MemcachedProfilerStorage.php

@@ -67,7 +67,7 @@ protected function getValue($key)
      */
     protected function setValue($key, $value, $expiration = 0)
     {
-        return $this->getMemcached()->set($key, $value, false, $expiration);
+        return $this->getMemcached()->set($key, $value, $expiration);
     }
 
     /**