Issue #2226437 followup by tstoeckler: [wrong patch committed] Create ContentEntityTypeInterface.

core/lib/Drupal/Core/Entity/ContentEntityType.php

@@ -8,7 +8,7 @@
 namespace Drupal\Core\Entity;
 
 /**
- * Defines a config entity type annotation object.
+ * Provides an implementation of a content entity type and its metadata.
  */
 class ContentEntityType extends EntityType implements ContentEntityTypeInterface {
 

core/lib/Drupal/Core/Entity/ContentEntityTypeInterface.php

@@ -8,8 +8,7 @@
 namespace Drupal\Core\Entity;
 
 /**
- * Provides an interface for a content entity type.
+ * Provides an interface for a content entity type and its metadata.
  */
-interface ContentEntityTypeInterface {
-
+interface ContentEntityTypeInterface extends EntityTypeInterface {
 }