diff --git a/core/lib/Drupal/Core/EventSubscriber/AttachedHeadersSubscriber.php b/core/lib/Drupal/Core/EventSubscriber/AttachedHeadersSubscriber.php
index 376786b..421b2df 100644
--- a/core/lib/Drupal/Core/EventSubscriber/AttachedHeadersSubscriber.php
+++ b/core/lib/Drupal/Core/EventSubscriber/AttachedHeadersSubscriber.php
@@ -28,6 +28,22 @@
 class AttachedHeadersSubscriber extends ResponseHeaderBag implements EventSubscriberInterface {
 
   /**
+   * Remove the Cache-Control header from this storage service.
+   *
+   * Our superclass adds a Cache-Control header automatically. However,
+   * FinishResponseSubscriber and others will deal with the Cache-Control
+   * header for the ResponseHeaderBag being output, and depend on this header
+   * not being set.
+   *
+   * @param array $headers
+   *   (optional) Initial headers.
+   */
+  public function __construct(array $headers = array()) {
+    parent::__construct($headers);
+    $this->remove('Cache-Control');
+  }
+
+  /**
    * Add attached headers to the final response object.
    *
    * @param Symfony\Component\HttpKernel\Event\FilterResponseEvent $event
@@ -38,24 +54,23 @@ public function onRespond(FilterResponseEvent $event) {
     if (!$event->isMasterRequest()) {
       return;
     }
-
     // Gather the response object from the event.
     $response = $event->getResponse();
-    // Add each of our headers to the response object's headers.
-    foreach ($this->getIterator() as $name => $value) {
-      // Symfony special-cases the 'Status' header.
-      if ($name === 'status') {
-        $response->setStatusCode($value);
-      }
-      $response->headers->set($name, $value, FALSE);
+    // Check for the 'status' special case.
+    if ($this->has('status')) {
+      $response->setStatusCode($this->get('status'));
+      $this->remove('status');
     }
+    $response->headers->add($this->all());
   }
 
   /**
    * {@inheritdoc}
    */
   public static function getSubscribedEvents() {
-    $events[KernelEvents::RESPONSE][] = array('onRespond');
+    // Set to low priority so that the render array has the last word on headers
+    // it specifies.
+    $events[KernelEvents::RESPONSE][] = array('onRespond', -1000);
     return $events;
   }
 
diff --git a/core/tests/Drupal/Tests/Core/EventSubscriber/AttachedHeadersSubscriberTest.php b/core/tests/Drupal/Tests/Core/EventSubscriber/AttachedHeadersSubscriberTest.php
index 42114c5..43896f7 100644
--- a/core/tests/Drupal/Tests/Core/EventSubscriber/AttachedHeadersSubscriberTest.php
+++ b/core/tests/Drupal/Tests/Core/EventSubscriber/AttachedHeadersSubscriberTest.php
@@ -15,7 +15,7 @@
  * @coversDefaultClass \Drupal\Core\EventSubscriber\AttachedHeadersSubscriber
  * @group EventSubscriber
  */
-class AttachedHeaderSubscriberTest extends UnitTestCase {
+class AttachedHeadersSubscriberTest extends UnitTestCase {
 
   public function providerOnRespond() {
     return [