[HttpKernel] HttpCache now sends maxage=0 cache-control directive in case of Esi presence.

src/Symfony/Component/HttpKernel/HttpCache/HttpCache.php

@@ -180,7 +180,7 @@ class HttpCache implements HttpKernelInterface
      */
     protected function addEsiTtl(Response $response)
     {
-        $this->esiTtls[] = $response->isValidateable() ? 0 : $response->getTtl();
+        $this->esiTtls[] = $response->isValidateable() ? -1 : $response->getTtl();
     }
 
     /**
@@ -192,10 +192,11 @@ class HttpCache implements HttpKernelInterface
     protected function updateResponseCacheControl(Response $response)
     {
         $ttl = min($this->esiTtls);
-        if (0 === $ttl) {
+        if (-1 === $ttl) {
             $response->headers->set('Cache-Control', 'no-cache, must-revalidate');
         } else {
             $response->setSharedMaxAge($ttl);
+            $response->setMaxAge(0);
         }
     }