diff --git a/core/modules/views/src/Plugin/views/filter/BooleanOperator.php b/core/modules/views/src/Plugin/views/filter/BooleanOperator.php
index 7f4a607..2508674 100644
--- a/core/modules/views/src/Plugin/views/filter/BooleanOperator.php
+++ b/core/modules/views/src/Plugin/views/filter/BooleanOperator.php
@@ -76,14 +76,14 @@ protected function operators() {
     return array(
       '=' => array(
         'title' => $this->t('Is equal to'),
-        'method' => 'queryOperatorBoolean',
+          'method' => '_queryOperatorBoolean',
         'short' => $this->t('='),
         'values' => 1,
         'query_operator' => static::EQUAL,
       ),
       '!=' => array(
         'title' => $this->t('Is not equal to'),
-        'method' => 'queryOperatorBoolean',
+        'method' => '_queryOperatorBoolean',
         'short' => $this->t('!='),
         'values' => 1,
         'query_operator' => static::NOT_EQUAL,
@@ -231,13 +231,9 @@ public function query() {
    *
    * @param string $field
    *   The field name to add the where condition for.
-   *
-   * @deprecated in Drupal 8.0.0, will be removed before Drupal 9.0.0.
-   *   Use Drupal\views\Plugin\views\filter\BooleanOperator::queryOperatorBoolean
-   *   instead.
    */
   protected function queryOpBoolean($field) {
-    $this->queryOperatorBoolean($field, static::EQUAL);
+    $this->_queryOperatorBoolean($field, static::EQUAL);
   }
 
   /**
@@ -247,8 +243,12 @@ protected function queryOpBoolean($field) {
    *   The field name to add the where condition for.
    * @param string $query_operator
    *   Either static::EQUAL or static::NOT_EQUAL.
+   *
+   * @internal
+   *   This method will be removed in 8.1.0 and is here to maintain backwards-
+   *   compatibility in 8.0.x releases.
    */
-  protected function queryOperatorBoolean($field, $query_operator) {
+  protected function _queryOperatorBoolean($field, $query_operator) {
     if (empty($this->value)) {
       if ($this->accept_null) {
         if ($query_operator == static::EQUAL) {