diff --git a/core/core.services.yml b/core/core.services.yml
index 6094635..8eccfa8 100644
--- a/core/core.services.yml
+++ b/core/core.services.yml
@@ -858,7 +858,7 @@ services:
   accept_negotiation_406:
     class: Drupal\Core\EventSubscriber\AcceptNegotiation406
     tags:
-      - { name: event_subscriber, priority: -10 }
+      - { name: event_subscriber}
   main_content_renderer.html:
     class: Drupal\Core\Render\MainContent\HtmlRenderer
     arguments: ['@title_resolver', '@plugin.manager.display_variant', '@event_dispatcher', '@element_info', '@module_handler', '@renderer', '@render_cache', '@cache_contexts_manager']
diff --git a/core/lib/Drupal/Core/EventSubscriber/AcceptNegotiation406.php b/core/lib/Drupal/Core/EventSubscriber/AcceptNegotiation406.php
index 4bfc942..72683e1 100644
--- a/core/lib/Drupal/Core/EventSubscriber/AcceptNegotiation406.php
+++ b/core/lib/Drupal/Core/EventSubscriber/AcceptNegotiation406.php
@@ -26,7 +26,7 @@ class AcceptNegotiation406 implements EventSubscriberInterface {
    * @param \Symfony\Component\HttpKernel\Event\GetResponseForControllerResultEvent $event
    *   The event to process.
    */
-  function onViewDetect406(GetResponseForControllerResultEvent $event) {
+  public function onViewDetect406(GetResponseForControllerResultEvent $event) {
     $request = $event->getRequest();
     $result = $event->getControllerResult();
 
diff --git a/core/misc/ajax.js b/core/misc/ajax.js
index b6864e7..c1dd726 100644
--- a/core/misc/ajax.js
+++ b/core/misc/ajax.js
@@ -296,7 +296,7 @@
   };
 
   /**
-   * Url query attribute to indicate the wrapper used to render a request.
+   * URL query attribute to indicate the wrapper used to render a request.
    *
    * This controls wrapping the HTML content for example in a modal dialog.
    */
diff --git a/core/modules/hal/hal.services.yml b/core/modules/hal/hal.services.yml
index 7e40df0..e817fbf 100644
--- a/core/modules/hal/hal.services.yml
+++ b/core/modules/hal/hal.services.yml
@@ -26,3 +26,7 @@ services:
     class: Drupal\hal\Encoder\JsonEncoder
     tags:
       - { name: encoder, priority: 10, format: hal_json }
+  exception.default_json:
+    class: Drupal\hal\EventSubscriber\ExceptionHalJsonSubscriber
+    tags:
+      - { name: event_subscriber }
diff --git a/core/modules/hal/src/EventSubscriber/ExceptionHalJsonSubscriber.php b/core/modules/hal/src/EventSubscriber/ExceptionHalJsonSubscriber.php
new file mode 100644
index 0000000..3bf3544
--- /dev/null
+++ b/core/modules/hal/src/EventSubscriber/ExceptionHalJsonSubscriber.php
@@ -0,0 +1,23 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\hal\EventSubscriber\ExceptionHalJsonSubscriber.
+ */
+
+namespace Drupal\hal\EventSubscriber;
+
+use Drupal\Core\EventSubscriber\ExceptionJsonSubscriber;
+
+/**
+ * Handle HAL exceptions the same as JSON exceptions.
+ */
+class ExceptionHalJsonSubscriber extends ExceptionJsonSubscriber {
+
+  /**
+   * {@inheritDoc}
+   */
+  protected function getHandledFormats() {
+    return ['hal_json'];
+  }
+}
diff --git a/core/modules/rest/src/Tests/ReadTest.php b/core/modules/rest/src/Tests/ReadTest.php
index c790302..3be342e 100644
--- a/core/modules/rest/src/Tests/ReadTest.php
+++ b/core/modules/rest/src/Tests/ReadTest.php
@@ -61,7 +61,7 @@ public function testRead() {
       $response = $this->httpRequest($entity_type . '/9999', 'GET', NULL, $this->defaultMimeType);
       $this->assertResponse(404);
       $path = $entity_type == 'node' ? '/node/{node}' : '/entity_test/{entity_test}';
-      $expected_message = Json::encode(['error' => 'A fatal error occurred: The "' . $entity_type . '" parameter was not converted for the path "' . $path . '" (route name: "rest.entity.' . $entity_type . '.GET.hal_json")']);
+      $expected_message = Json::encode(['message' => 'The "' . $entity_type . '" parameter was not converted for the path "' . $path . '" (route name: "rest.entity.' . $entity_type . '.GET.hal_json")']);
       $this->assertIdentical($expected_message, $response, 'Response message is correct.');
 
       // Make sure that field level access works and that the according field is
@@ -81,7 +81,7 @@ public function testRead() {
       $this->drupalLogout();
       $response = $this->httpRequest($entity->urlInfo(), 'GET', NULL, $this->defaultMimeType);
       $this->assertResponse(403);
-      $this->assertIdentical('{}', $response);
+      $this->assertIdentical('{"message":""}', $response);
     }
     // Try to read a resource which is not REST API enabled.
     $account = $this->drupalCreateUser();
@@ -93,7 +93,7 @@ public function testRead() {
     // used, but it can't render into application/hal+json, so it returns a 406.
     $this->assertResponse('406', 'HTTP response code is 406 when the resource does not define formats, because it falls back to the canonical, non-REST route.');
     $this->assertEqual($response, Json::encode([
-      'error' => 'A fatal error occurred: Not acceptable',
+      'message' => 'Not acceptable',
     ]));
   }