diff --git a/core/lib/Drupal/Core/EventSubscriber/SpecialAttributesRouteSubscriber.php b/core/lib/Drupal/Core/EventSubscriber/SpecialAttributesRouteSubscriber.php
index f5bf1f4..22e82d2 100644
--- a/core/lib/Drupal/Core/EventSubscriber/SpecialAttributesRouteSubscriber.php
+++ b/core/lib/Drupal/Core/EventSubscriber/SpecialAttributesRouteSubscriber.php
@@ -43,9 +43,13 @@ public function onRouteBuilding(RouteBuildEvent $event) {
 
     foreach ($event->getRouteCollection()->all() as $route) {
       if ($not_allowed_variables = array_intersect($route->compile()->getVariables(), $special_variables)) {
-        throw new \InvalidArgumentException(String::format('The following variables are reserved names by drupal: @variables', array('@variables' => implode(', ', $not_allowed_variables))));
+        $placeholders = array('@variables' => implode(', ', $not_allowed_variables));
+        drupal_set_message(String::format('The following variables are reserved names by drupal: @variables', $placeholders));
+        watchdog('error', 'The following variables are reserved names by drupal: @variables', $placeholders);
+        return FALSE;
       }
     }
+    return TRUE;
   }
 
   /**
diff --git a/core/tests/Drupal/Tests/Core/EventSubscriber/SpecialAttributesRouteSubscriberTest.php b/core/tests/Drupal/Tests/Core/EventSubscriber/SpecialAttributesRouteSubscriberTest.php
index f5f8f25..7555768 100644
--- a/core/tests/Drupal/Tests/Core/EventSubscriber/SpecialAttributesRouteSubscriberTest.php
+++ b/core/tests/Drupal/Tests/Core/EventSubscriber/SpecialAttributesRouteSubscriberTest.php
@@ -5,7 +5,7 @@
  * Contains \Drupal\Tests\Core\EventSubscriber\SpecialAttributesRouteSubscriberTest.
  */
 
-namespace Drupal\Tests\Core\EventSubscriber;
+namespace Drupal\Tests\Core\EventSubscriber {
 
 use Drupal\Core\EventSubscriber\SpecialAttributesRouteSubscriber;
 use Drupal\Core\Routing\RouteBuildEvent;
@@ -95,7 +95,7 @@ public function testOnRouteBuildingValidVariables(Route $route) {
     $route_collection = new RouteCollection();
     $route_collection->add('test', $route);
     $event = new RouteBuildEvent($route_collection, 'test');
-    $this->specialAttributesRouteSubscriber->onRouteBuilding($event);
+    $this->assertTrue($this->specialAttributesRouteSubscriber->onRouteBuilding($event));
   }
 
   /**
@@ -105,14 +105,25 @@ public function testOnRouteBuildingValidVariables(Route $route) {
    *   The route to check.
    *
    * @dataProvider providerTestOnRouteBuildingInvalidVariables
-   *
-   * @expectedException \InvalidArgumentException
    */
   public function testOnRouteBuildingInvalidVariables(Route $route) {
     $route_collection = new RouteCollection();
     $route_collection->add('test', $route);
     $event = new RouteBuildEvent($route_collection, 'test');
-    $this->specialAttributesRouteSubscriber->onRouteBuilding($event);
+    $this->assertFalse($this->specialAttributesRouteSubscriber->onRouteBuilding($event));
   }
 
 }
+
+}
+
+namespace {
+  if (!function_exists('watchdog')) {
+    function watchdog($type, $message, array $args = NULL) {
+    }
+  }
+  if (!function_exists('drupal_set_message')) {
+    function drupal_set_message($type = NULL, $message = '') {
+    }
+  }
+}