diff --git a/core/lib/Drupal/Core/Theme/MissingThemeDependencyException.php b/core/lib/Drupal/Core/Theme/MissingThemeDependencyException.php
index c3f72af..0708450 100644
--- a/core/lib/Drupal/Core/Theme/MissingThemeDependencyException.php
+++ b/core/lib/Drupal/Core/Theme/MissingThemeDependencyException.php
@@ -11,7 +11,6 @@
  * Exception to be thrown when base theme for installed theme is not installed.
  *
  * @see \Drupal\Core\Theme\ThemeInitialization::getActiveThemeByName().
- * @see \Drupal\system\Controller\DbUpdateController::ensureActiveThemeDependencies().
  */
 class MissingThemeDependencyException extends \Exception {
 
diff --git a/core/lib/Drupal/Core/Theme/ThemeInitialization.php b/core/lib/Drupal/Core/Theme/ThemeInitialization.php
index e1cd44c..d0c9166 100644
--- a/core/lib/Drupal/Core/Theme/ThemeInitialization.php
+++ b/core/lib/Drupal/Core/Theme/ThemeInitialization.php
@@ -111,10 +111,10 @@ public function getActiveThemeByName($theme_name) {
       $ancestor = $themes[$ancestor]->base_theme;
       if (!$this->themeHandler->themeExists($ancestor)) {
         if ($ancestor == 'stable') {
-          // Themes that depend on Stable will be fixed by system_update_8012()
-          // and system_update_8014(). There is no harm in not adding it as an
-          // ancestor since at worst some people might experience slight visual
-          // regressions on the update.php
+          // Themes that depend on Stable will be fixed by system_update_8014().
+          // There is no harm in not adding it as an ancestor since at worst
+          // some people might experience slight visual regressions on
+          // update.php.
           continue;
         }
         throw new MissingThemeDependencyException(sprintf('Base theme %s has not been installed.', $ancestor), $ancestor);