diff --git a/core/modules/ckeditor/lib/Drupal/ckeditor/CKEditorPluginBase.php b/core/modules/ckeditor/lib/Drupal/ckeditor/CKEditorPluginBase.php
index 67a11e6..445d9c4 100644
--- a/core/modules/ckeditor/lib/Drupal/ckeditor/CKEditorPluginBase.php
+++ b/core/modules/ckeditor/lib/Drupal/ckeditor/CKEditorPluginBase.php
@@ -30,7 +30,7 @@
  * @see CKEditorPluginContextualInterface
  * @see CKEditorPluginConfigurableInterface
  */
-abstract class CKEditorPluginBase extends PluginBase implements CKEditorPluginInterface {
+abstract class CKEditorPluginBase extends PluginBase implements CKEditorPluginInterface, CKEditorPluginButtonsInterface {
 
   /**
    * Implements \Drupal\ckeditor\Plugin\CKEditorPluginInterface::isInternal().
@@ -52,11 +52,4 @@ function getDependencies(Editor $editor) {
   function getLibraries(Editor $editor) {
     return array();
   }
-
-  /**
-   * Implements \Drupal\ckeditor\Plugin\CKEditorPluginInterface::getConfig().
-   */
-  function getConfig(Editor $editor) {
-    return array();
-  }
 }
diff --git a/core/modules/ckeditor/lib/Drupal/ckeditor/Plugin/ckeditor/plugin/DrupalImage.php b/core/modules/ckeditor/lib/Drupal/ckeditor/Plugin/ckeditor/plugin/DrupalImage.php
index 663c4f0..dcaa7b5 100644
--- a/core/modules/ckeditor/lib/Drupal/ckeditor/Plugin/ckeditor/plugin/DrupalImage.php
+++ b/core/modules/ckeditor/lib/Drupal/ckeditor/Plugin/ckeditor/plugin/DrupalImage.php
@@ -8,7 +8,6 @@
 namespace Drupal\ckeditor\Plugin\ckeditor\plugin;
 
 use Drupal\ckeditor\CKEditorPluginBase;
-use Drupal\ckeditor\CKEditorPluginButtonsInterface;
 use Drupal\Core\Annotation\Plugin;
 use Drupal\Core\Annotation\Translation;
 use Drupal\editor\Plugin\Core\Entity\Editor;
@@ -22,7 +21,7 @@
  *   module = "ckeditor"
  * )
  */
-class DrupalImage extends CKEditorPluginBase implements CKEditorPluginButtonsInterface {
+class DrupalImage extends CKEditorPluginBase {
 
   /**
    * Implements \Drupal\ckeditor\Plugin\CKEditorPluginInterface::getFile().
diff --git a/core/modules/ckeditor/lib/Drupal/ckeditor/Plugin/ckeditor/plugin/Internal.php b/core/modules/ckeditor/lib/Drupal/ckeditor/Plugin/ckeditor/plugin/Internal.php
index 4988893..39af63c 100644
--- a/core/modules/ckeditor/lib/Drupal/ckeditor/Plugin/ckeditor/plugin/Internal.php
+++ b/core/modules/ckeditor/lib/Drupal/ckeditor/Plugin/ckeditor/plugin/Internal.php
@@ -8,7 +8,6 @@
 namespace Drupal\ckeditor\Plugin\ckeditor\plugin;
 
 use Drupal\ckeditor\CKEditorPluginBase;
-use Drupal\ckeditor\CKEditorPluginButtonsInterface;
 use Drupal\Component\Utility\NestedArray;
 use Drupal\Core\Annotation\Plugin;
 use Drupal\Core\Annotation\Translation;
@@ -23,7 +22,7 @@
  *   module = "ckeditor"
  * )
  */
-class Internal extends CKEditorPluginBase implements CKEditorPluginButtonsInterface {
+class Internal extends CKEditorPluginBase {
 
   /**
    * Implements \Drupal\ckeditor\Plugin\CKEditorPluginInterface::isInternal().
diff --git a/core/modules/ckeditor/lib/Drupal/ckeditor/Plugin/ckeditor/plugin/StylesCombo.php b/core/modules/ckeditor/lib/Drupal/ckeditor/Plugin/ckeditor/plugin/StylesCombo.php
index ec00a9a..9f09a11 100644
--- a/core/modules/ckeditor/lib/Drupal/ckeditor/Plugin/ckeditor/plugin/StylesCombo.php
+++ b/core/modules/ckeditor/lib/Drupal/ckeditor/Plugin/ckeditor/plugin/StylesCombo.php
@@ -8,7 +8,6 @@
 namespace Drupal\ckeditor\Plugin\ckeditor\plugin;
 
 use Drupal\ckeditor\CKEditorPluginBase;
-use Drupal\ckeditor\CKEditorPluginButtonsInterface;
 use Drupal\ckeditor\CKEditorPluginConfigurableInterface;
 use Drupal\Component\Utility\NestedArray;
 use Drupal\Core\Annotation\Plugin;
@@ -24,7 +23,7 @@
  *   module = "ckeditor"
  * )
  */
-class StylesCombo extends CKEditorPluginBase implements CKEditorPluginButtonsInterface, CKEditorPluginConfigurableInterface {
+class StylesCombo extends CKEditorPluginBase implements CKEditorPluginConfigurableInterface {
 
   /**
    * Implements \Drupal\ckeditor\Plugin\CKEditorPluginInterface::isInternal().
diff --git a/core/modules/ckeditor/tests/modules/lib/Drupal/ckeditor_test/Plugin/ckeditor/plugin/Llama.php b/core/modules/ckeditor/tests/modules/lib/Drupal/ckeditor_test/Plugin/ckeditor/plugin/Llama.php
index 029099e..9ce164b 100644
--- a/core/modules/ckeditor/tests/modules/lib/Drupal/ckeditor_test/Plugin/ckeditor/plugin/Llama.php
+++ b/core/modules/ckeditor/tests/modules/lib/Drupal/ckeditor_test/Plugin/ckeditor/plugin/Llama.php
@@ -7,8 +7,8 @@
 
 namespace Drupal\ckeditor_test\Plugin\ckeditor\plugin;
 
-use Drupal\ckeditor\CKEditorPluginBase;
 use Drupal\ckeditor\CKEditorPluginInterface;
+use Drupal\Component\Plugin\PluginBase;
 use Drupal\Core\Annotation\Plugin;
 use Drupal\Core\Annotation\Translation;
 use Drupal\editor\Plugin\Core\Entity\Editor;
@@ -31,7 +31,28 @@
  *   module = "ckeditor_test"
  * )
  */
-class Llama extends CKEditorPluginBase {
+class Llama extends PluginBase implements CKEditorPluginInterface {
+
+  /**
+   * Implements \Drupal\ckeditor\Plugin\CKEditorPluginInterface::isInternal().
+   */
+  function isInternal() {
+    return FALSE;
+  }
+
+  /**
+   * Implements \Drupal\ckeditor\Plugin\CKEditorPluginInterface::getDependencies().
+   */
+  function getDependencies(Editor $editor) {
+    return array();
+  }
+
+  /**
+   * Implements \Drupal\ckeditor\Plugin\CKEditorPluginInterface::getLibraries().
+   */
+  function getLibraries(Editor $editor) {
+    return array();
+  }
 
   /**
    * Implements \Drupal\ckeditor\Plugin\CKEditorPluginInterface::getFile().
@@ -40,4 +61,11 @@ function getFile() {
     return drupal_get_path('module', 'ckeditor_test') . '/js/llama.js';
   }
 
+  /**
+   * Implements \Drupal\ckeditor\Plugin\CKEditorPluginInterface::getConfig().
+   */
+  public function getConfig(Editor $editor) {
+    return array();
+  }
+
 }