diff --git a/core/modules/node/lib/Drupal/node/Plugin/views/argument_validator/Node.php b/core/modules/node/lib/Drupal/node/Plugin/views/argument_validator/Node.php
index a2b8b635524c1849136e448efe63334cad59ea8d..023462999b97fa4ed7a8a23b0929ac4e561b6069 100644
--- a/core/modules/node/lib/Drupal/node/Plugin/views/argument_validator/Node.php
+++ b/core/modules/node/lib/Drupal/node/Plugin/views/argument_validator/Node.php
@@ -80,7 +80,7 @@ public function submitOptionsForm(&$form, &$form_state, &$options = array()) {
     $options['types'] = array_filter($options['types']);
   }
 
-  function validate_argument($argument) {
+  public function validateArgument($argument) {
     $types = $this->options['types'];
 
     switch ($this->options['nid_type']) {
diff --git a/core/modules/taxonomy/lib/Drupal/taxonomy/Plugin/views/argument_validator/Term.php b/core/modules/taxonomy/lib/Drupal/taxonomy/Plugin/views/argument_validator/Term.php
index b93aa87d6264158b54d7fbb33e5003c84a736ca9..7491199e8bd84e2629d99782db2f8efd7341f7d6 100644
--- a/core/modules/taxonomy/lib/Drupal/taxonomy/Plugin/views/argument_validator/Term.php
+++ b/core/modules/taxonomy/lib/Drupal/taxonomy/Plugin/views/argument_validator/Term.php
@@ -93,7 +93,7 @@ public function submitOptionsForm(&$form, &$form_state, &$options = array()) {
     $options['vids'] = array_filter($options['vids']);
   }
 
-  function validate_argument($argument) {
+  public function validateArgument($argument) {
     $vocabularies = array_filter($this->options['vids']);
     $type = $this->options['type'];
     $transform = $this->options['transform'];
diff --git a/core/modules/user/lib/Drupal/user/Plugin/views/argument_validator/User.php b/core/modules/user/lib/Drupal/user/Plugin/views/argument_validator/User.php
index cc518c339e87ee953bc3eb288038078aa5923c7f..764efde4fbba0c27333c850e2dbf2122c66d804d 100644
--- a/core/modules/user/lib/Drupal/user/Plugin/views/argument_validator/User.php
+++ b/core/modules/user/lib/Drupal/user/Plugin/views/argument_validator/User.php
@@ -72,7 +72,7 @@ public function submitOptionsForm(&$form, &$form_state, &$options = array()) {
     $options['roles'] = array_filter($options['roles']);
   }
 
-  function validate_argument($argument) {
+  public function validateArgument($argument) {
     $type = $this->options['type'];
     // is_numeric() can return false positives, so we ensure it's an integer.
     // However, is_integer() will always fail, since $argument is a string.
diff --git a/core/modules/views/lib/Drupal/views/Plugin/views/argument/ArgumentPluginBase.php b/core/modules/views/lib/Drupal/views/Plugin/views/argument/ArgumentPluginBase.php
index dd861905fba9e11588013de44abf848ad20b53cc..49743800506eb71ec73da79962342ee6e205b408 100644
--- a/core/modules/views/lib/Drupal/views/Plugin/views/argument/ArgumentPluginBase.php
+++ b/core/modules/views/lib/Drupal/views/Plugin/views/argument/ArgumentPluginBase.php
@@ -950,7 +950,7 @@ public function validateArgument($arg) {
     }
 
     $plugin = $this->getPlugin('argument_validator');
-    return $this->argument_validated = $plugin->validate_argument($arg);
+    return $this->argument_validated = $plugin->validateArgument($arg);
   }
 
   /**
@@ -960,7 +960,7 @@ public function validateArgument($arg) {
    * argument fails to validate, but there is an action to take anyway,
    * then validation cannot actually fail.
    */
-  function validate_argument($arg) {
+  public function validateMenuArgument($arg) {
     $validate_info = $this->defaultActions($this->options['validate']['fail']);
     if (empty($validate_info['hard fail'])) {
       return TRUE;
diff --git a/core/modules/views/lib/Drupal/views/Plugin/views/argument_validator/ArgumentValidatorPluginBase.php b/core/modules/views/lib/Drupal/views/Plugin/views/argument_validator/ArgumentValidatorPluginBase.php
index e7945dc6a47ae2af5bbb0cc8a5496e38edc5c9e7..af7f12cd244e5f09a6447d85cf657e05bcd41eb9 100644
--- a/core/modules/views/lib/Drupal/views/Plugin/views/argument_validator/ArgumentValidatorPluginBase.php
+++ b/core/modules/views/lib/Drupal/views/Plugin/views/argument_validator/ArgumentValidatorPluginBase.php
@@ -80,7 +80,7 @@ protected function checkAccess(&$form, $option_name) {
     }
   }
 
-  function validate_argument($arg) { return TRUE; }
+  public function validateArgument($arg) { return TRUE; }
 
   /**
    * Process the summary arguments for displaying.
diff --git a/core/modules/views/lib/Drupal/views/Plugin/views/argument_validator/None.php b/core/modules/views/lib/Drupal/views/Plugin/views/argument_validator/None.php
index 7a63069a50925f4e2ea5956300180afd9e4bf2aa..c8aa8ebaf5803da477c06a7ee4c1da3f95dd78de 100644
--- a/core/modules/views/lib/Drupal/views/Plugin/views/argument_validator/None.php
+++ b/core/modules/views/lib/Drupal/views/Plugin/views/argument_validator/None.php
@@ -22,7 +22,7 @@
  */
 class None extends ArgumentValidatorPluginBase {
 
-  function validate_argument($argument) {
+  public function validateArgument($argument) {
     if (!empty($this->argument->options['must_not_be'])) {
       return !isset($argument);
     }
diff --git a/core/modules/views/lib/Drupal/views/Plugin/views/argument_validator/Numeric.php b/core/modules/views/lib/Drupal/views/Plugin/views/argument_validator/Numeric.php
index 6db339ea04c11a3b17cbf8ce4e744b1755a657e8..05b7845c587d480161dfdb3bef68fe932eeaa4db 100644
--- a/core/modules/views/lib/Drupal/views/Plugin/views/argument_validator/Numeric.php
+++ b/core/modules/views/lib/Drupal/views/Plugin/views/argument_validator/Numeric.php
@@ -22,7 +22,7 @@
  */
 class Numeric extends ArgumentValidatorPluginBase {
 
-  function validate_argument($argument) {
+  public function validateArgument($argument) {
     return is_numeric($argument);
   }
 
diff --git a/core/modules/views/lib/Drupal/views/Plugin/views/argument_validator/Php.php b/core/modules/views/lib/Drupal/views/Plugin/views/argument_validator/Php.php
index dc16a1c87a19e0b7619efdcca9421ab57bbd58b4..138a1dff1e99dff5b8b582d17483c3b1afb82fd7 100644
--- a/core/modules/views/lib/Drupal/views/Plugin/views/argument_validator/Php.php
+++ b/core/modules/views/lib/Drupal/views/Plugin/views/argument_validator/Php.php
@@ -49,7 +49,7 @@ public function access() {
     return user_access('use PHP for settings');
   }
 
-  function validate_argument($argument) {
+  public function validateArgument($argument) {
     // set up variables to make it easier to reference during the argument.
     $view = &$this->view;
     $handler = &$this->argument;
diff --git a/core/modules/views/views.module b/core/modules/views/views.module
index d755506b2a8e6619311f563d9d9af9bfd9f37a79..4d656b64ebc8f429f54e3c2ddd20e4f13fce0188 100644
--- a/core/modules/views/views.module
+++ b/core/modules/views/views.module
@@ -404,7 +404,7 @@ function views_arg_load($value, $name, $display_id, $index) {
 
     if (isset($indexes[$index])) {
       if (isset($view->argument[$indexes[$index]])) {
-        $arg = $view->argument[$indexes[$index]]->validate_argument($value) ? $value : FALSE;
+        $arg = $view->argument[$indexes[$index]]->validateMenuArgument($value) ? $value : FALSE;
         $view->destroy();
 
         // Store the output in case we load this same menu item again.