diff -u b/core/lib/Drupal/Component/Plugin/PluginManagerBase.php b/core/lib/Drupal/Component/Plugin/PluginManagerBase.php
--- b/core/lib/Drupal/Component/Plugin/PluginManagerBase.php
+++ b/core/lib/Drupal/Component/Plugin/PluginManagerBase.php
@@ -69,7 +69,7 @@
   }
 
   /**
-   * Implements Drupal\Component\Plugin\PluginManagerInterface::clearCachedDefinitions().
+   * Implements Drupal\Component\Plugin\Discovery\CachedDiscoveryInterface::clearCachedDefinitions().
    */
   public function clearCachedDefinitions() {
     if ($this->discovery instanceof CachedDiscoveryInterface) {
diff -u b/core/lib/Drupal/Core/Plugin/Discovery/CacheDecorator.php b/core/lib/Drupal/Core/Plugin/Discovery/CacheDecorator.php
--- b/core/lib/Drupal/Core/Plugin/Discovery/CacheDecorator.php
+++ b/core/lib/Drupal/Core/Plugin/Discovery/CacheDecorator.php
@@ -110,7 +110,7 @@
   }
 
   /**
-   * Clears the cached plugin definitions.
+   * Implements Drupal\Component\Plugin\Discovery\CachedDiscoveryInterface::clearCachedDefinitions.
    */
   public function clearCachedDefinitions() {
     if (isset($this->cacheKey)) {