diff --git a/core/modules/views/src/Plugin/views/filter/BooleanOperator.php b/core/modules/views/src/Plugin/views/filter/BooleanOperator.php
index a4cded4..7f4a607 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' => 'queryOpBoolean',
+        'method' => 'queryOperatorBoolean',
         'short' => $this->t('='),
         'values' => 1,
         'query_operator' => static::EQUAL,
       ),
       '!=' => array(
         'title' => $this->t('Is not equal to'),
-        'method' => 'queryOpBoolean',
+        'method' => 'queryOperatorBoolean',
         'short' => $this->t('!='),
         'values' => 1,
         'query_operator' => static::NOT_EQUAL,
@@ -226,15 +226,29 @@ public function query() {
   }
 
   /**
+   * Adds a where condition to the query for a boolean value. This function
+   * remains to prevent breaks in public-facing API's.
+   *
+   * @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);
+  }
+
+  /**
    * Adds a where condition to the query for a boolean value.
    *
    * @param string $field
    *   The field name to add the where condition for.
    * @param string $query_operator
-   *   (optional) Either static::EQUAL or static::NOT_EQUAL. Defaults to
-   *   static::EQUAL.
+   *   Either static::EQUAL or static::NOT_EQUAL.
    */
-  protected function queryOpBoolean($field, $query_operator = EQUAL) {
+  protected function queryOperatorBoolean($field, $query_operator) {
     if (empty($this->value)) {
       if ($this->accept_null) {
         if ($query_operator == static::EQUAL) {