diff --git a/core/modules/views/lib/Drupal/views/Plugin/views/argument/ArgumentPluginBase.php b/core/modules/views/lib/Drupal/views/Plugin/views/argument/ArgumentPluginBase.php
index 1e98186d0d06..3bf73676af9f 100644
--- a/core/modules/views/lib/Drupal/views/Plugin/views/argument/ArgumentPluginBase.php
+++ b/core/modules/views/lib/Drupal/views/Plugin/views/argument/ArgumentPluginBase.php
@@ -449,7 +449,7 @@ abstract class ArgumentPluginBase extends HandlerBase {
       'default' => array(
         'title' => t('Provide default value'),
         'method' => 'default_default',
-        'form method' => 'default_argument_form',
+        'form method' => 'defaultArgumentForm',
         'has default argument' => TRUE,
         'default only' => TRUE, // this can only be used for missing argument, not validation failure
         'breadcrumb' => TRUE, // generate a breadcrumb to here
@@ -496,7 +496,7 @@ abstract class ArgumentPluginBase extends HandlerBase {
    * Provide a form for selecting the default argument when the
    * default action is set to provide default argument.
    */
-  function default_argument_form(&$form, &$form_state) {
+  public function defaultArgumentForm(&$form, &$form_state) {
     $plugins = Views::pluginManager('argument_default')->getDefinitions();
     $options = array();
 
diff --git a/core/modules/views/lib/Drupal/views/Plugin/views/argument/Date.php b/core/modules/views/lib/Drupal/views/Plugin/views/argument/Date.php
index e9a64e221eca..2abda36a2e7b 100644
--- a/core/modules/views/lib/Drupal/views/Plugin/views/argument/Date.php
+++ b/core/modules/views/lib/Drupal/views/Plugin/views/argument/Date.php
@@ -47,8 +47,8 @@ class Date extends Formula {
   /**
    * Add an option to set the default value to the current date.
    */
-  function default_argument_form(&$form, &$form_state) {
-    parent::default_argument_form($form, $form_state);
+  public function defaultArgumentForm(&$form, &$form_state) {
+    parent::defaultArgumentForm($form, $form_state);
     $form['default_argument_type']['#options'] += array('date' => t('Current date'));
     $form['default_argument_type']['#options'] += array('node_created' => t("Current node's creation time"));
     $form['default_argument_type']['#options'] += array('node_changed' => t("Current node's update time"));  }