diff --git a/core/lib/Drupal/Core/Form/FormBuilder.php b/core/lib/Drupal/Core/Form/FormBuilder.php
index 1046499..974d309 100644
--- a/core/lib/Drupal/Core/Form/FormBuilder.php
+++ b/core/lib/Drupal/Core/Form/FormBuilder.php
@@ -857,7 +857,7 @@ public function validateForm($form_id, &$form, &$form_state) {
     // Recursively validate each form element.
     $this->doValidateForm($form, $form_state, $form_id);
     // After validation, loop through and assign each element its errors.
-    $this->doCheckErrors($form, $form_state);
+    $this->setElementErrorsFromFormState($form, $form_state);
     // Mark this form as validated.
     $this->validatedForms[$form_id] = TRUE;
 
@@ -1157,11 +1157,11 @@ protected function doValidateForm(&$elements, &$form_state, $form_id = NULL) {
    * @param array $form_state
    *   An associative array containing the current state of the form.
    */
-  protected function doCheckErrors(array &$elements, array &$form_state) {
+  protected function setElementErrorsFromFormState(array &$elements, array &$form_state) {
     // Recurse through all children.
     foreach ($this->elementChildren($elements) as $key) {
       if (isset($elements[$key]) && $elements[$key]) {
-        $this->doCheckErrors($elements[$key], $form_state);
+        $this->setElementErrorsFromFormState($elements[$key], $form_state);
       }
     }
     // Store the errors for this element on the element directly.
diff --git a/core/lib/Drupal/Core/Form/FormBuilderInterface.php b/core/lib/Drupal/Core/Form/FormBuilderInterface.php
index 6e580c7..2144065 100644
--- a/core/lib/Drupal/Core/Form/FormBuilderInterface.php
+++ b/core/lib/Drupal/Core/Form/FormBuilderInterface.php
@@ -513,14 +513,14 @@ public function executeHandlers($type, &$form, &$form_state);
    *
    * When a validation error is detected, the validator calls form_set_error()
    * to indicate which element needs to be changed and provide an error message.
-   * This causes the Form API to not execute the form submit handlers, $form_state, and
+   * This causes the Form API to not execute the form submit handlers, and
    * instead to re-display the form to the user with the corresponding elements
    * rendered with an 'error' CSS class (shown as red by default).
    *
    * The standard form_set_error() behavior can be changed if a button provides
    * the #limit_validation_errors property. Multistep forms not wanting to
    * validate the whole form can set #limit_validation_errors on buttons to
-   * limit validation errors to only certain elements. For example, $form_state, pressing the
+   * limit validation errors to only certain elements. For example, pressing the
    * "Previous" button in a multistep form should not fire validation errors
    * just because the current step has invalid values. If
    * #limit_validation_errors is set on a clicked button, the button must also
@@ -567,12 +567,13 @@ public function executeHandlers($type, &$form, &$form_state);
    * This will require $form_state['values']['step1'] and everything within it
    * (for example, $form_state['values']['step1']['choice']) to be valid, so
    * calls to form_set_error('step1', $form_state, $message) or
-   * form_set_error('step1][choice', $form_state, $message) will prevent the submit handlers
-   * from running, and result in the error message being displayed to the user.
-   * However, calls to form_set_error('step2', $form_state, $message) and
-   * form_set_error('step2][groupX][choiceY', $form_state, $message) will be suppressed,
-   * resulting in the message not being displayed to the user, and the submit
-   * handlers will run despite $form_state['values']['step2'] and
+   * form_set_error('step1][choice', $form_state, $message) will prevent the
+   * submit handlers from running, and result in the error message being
+   * displayed to the user. However, calls to
+   * form_set_error('step2', $form_state, $message) and
+   * form_set_error('step2][groupX][choiceY', $form_state, $message) will be
+   * suppressed, resulting in the message not being displayed to the user, and
+   * the submitdoCheckErrors handlers will run despite $form_state['values']['step2'] and
    * $form_state['values']['step2']['groupX']['choiceY'] containing invalid
    * values. Errors for an invalid $form_state['values']['foo'] will be
    * suppressed, but errors flagging invalid values for