diff --git a/core/modules/views/lib/Drupal/views/ViewExecutable.php b/core/modules/views/lib/Drupal/views/ViewExecutable.php
index 898503f..b935181 100644
--- a/core/modules/views/lib/Drupal/views/ViewExecutable.php
+++ b/core/modules/views/lib/Drupal/views/ViewExecutable.php
@@ -1881,6 +1881,7 @@ public static function viewsHandlerTypes() {
    *   An array of plugin type strings.
    */
   public static function getPluginTypes() {
+    // As this is used during container building, this must be constant.
     return array(
       'access',
       'area',
diff --git a/core/modules/views/lib/Drupal/views/ViewsBundle.php b/core/modules/views/lib/Drupal/views/ViewsBundle.php
index 0b18d3f..393851e 100644
--- a/core/modules/views/lib/Drupal/views/ViewsBundle.php
+++ b/core/modules/views/lib/Drupal/views/ViewsBundle.php
@@ -21,6 +21,7 @@ class ViewsBundle extends Bundle {
    * Overrides Symfony\Component\HttpKernel\Bundle\Bundle::build().
    */
   public function build(ContainerBuilder $container) {
+    // This is working only because getPluginTypes wraps a constant array.
     foreach (ViewExecutable::getPluginTypes() as $type) {
       $container->register("plugin.manager.views.$type", 'Drupal\views\Plugin\ViewsPluginManager')
         ->addArgument($type)