Issue #3500483: add cache contexts in applies()

src/EasyBreadcrumbBuilder.php

@@ -11,6 +11,7 @@ use Drupal\Core\Access\AccessManagerInterface;
 use Drupal\Core\Breadcrumb\Breadcrumb;
 use Drupal\Core\Breadcrumb\BreadcrumbBuilderInterface;
 use Drupal\Core\Cache\CacheableDependencyInterface;
+use Drupal\Core\Cache\CacheableMetadata;
 use Drupal\Core\Config\ConfigFactoryInterface;
 use Drupal\Core\Controller\TitleResolverInterface;
 use Drupal\Core\Entity\EntityInterface;
@@ -244,7 +245,12 @@ class EasyBreadcrumbBuilder implements BreadcrumbBuilderInterface {
   /**
    * {@inheritdoc}
    */
-  public function applies(RouteMatchInterface $route_match) {
+  public function applies(RouteMatchInterface $route_match, ?CacheableMetadata $cacheable_metadata = NULL) {
+
+    // @todo Remove null safe operator in Drupal 12.0.0, see
+    //   https://www.drupal.org/project/drupal/issues/3459277.
+    $cacheable_metadata?->addCacheContexts(['route', 'url.path', 'languages']);
+
     $applies_admin_routes = $this->config->get(EasyBreadcrumbConstants::APPLIES_ADMIN_ROUTES);
 
     // If never set before ensure Applies to administration pages is on.
@@ -447,6 +453,8 @@ class EasyBreadcrumbBuilder implements BreadcrumbBuilderInterface {
         }
 
         // Expire cache by languages and config changes.
+        // @todo Remove in Drupal 12.0.0, will be added from ::applies(). See
+        //   https://www.drupal.org/project/drupal/issues/3459277
         $breadcrumb->addCacheContexts(['route', 'url.path', 'languages']);
 
         // Expire cache context for config changes.