diff -u b/core/lib/Drupal/Core/Entity/ContentEntityStorageBase.php b/core/lib/Drupal/Core/Entity/ContentEntityStorageBase.php
--- b/core/lib/Drupal/Core/Entity/ContentEntityStorageBase.php
+++ b/core/lib/Drupal/Core/Entity/ContentEntityStorageBase.php
@@ -16,7 +16,7 @@
 /**
  * Base class for content entity storage handlers.
  */
-abstract class ContentEntityStorageBase extends EntityStorageBase implements ContentEntityStorageInterface {
+abstract class ContentEntityStorageBase extends EntityStorageBase implements ContentEntityStorageInterface, DynamicallyFieldableEntityStorageInterface {
 
   /**
    * The entity bundle key.
diff -u b/core/lib/Drupal/Core/Entity/ContentEntityStorageInterface.php b/core/lib/Drupal/Core/Entity/ContentEntityStorageInterface.php
--- b/core/lib/Drupal/Core/Entity/ContentEntityStorageInterface.php
+++ b/core/lib/Drupal/Core/Entity/ContentEntityStorageInterface.php
@@ -10,7 +10,7 @@
 /**
  * A storage that supports content entity types.
  */
-interface ContentEntityStorageInterface extends DynamicallyFieldableEntityStorageInterface {
+interface ContentEntityStorageInterface extends EntityStorageInterface {
 
   /**
    * Constructs a new entity translation object, without permanently saving it.
diff -u b/core/lib/Drupal/Core/Entity/KeyValueStore/KeyValueContentEntityStorage.php b/core/lib/Drupal/Core/Entity/KeyValueStore/KeyValueContentEntityStorage.php
--- b/core/lib/Drupal/Core/Entity/KeyValueStore/KeyValueContentEntityStorage.php
+++ b/core/lib/Drupal/Core/Entity/KeyValueStore/KeyValueContentEntityStorage.php
@@ -9,8 +9,6 @@
 
 use Drupal\Core\Entity\ContentEntityInterface;
 use Drupal\Core\Entity\ContentEntityStorageInterface;
-use Drupal\Core\Field\FieldDefinitionInterface;
-use Drupal\Core\Field\FieldStorageDefinitionInterface;
 
 /**
  * Provides a key value backend for content entities.
@@ -21,55 +19,7 @@
    * {@inheritdoc}
    */
-  public function countFieldData($storage_definition, $as_bool = FALSE) {}
-
-  /**
-   * {@inheritdoc}
-   */
-  public function hasData() {}
-
-  /**
-   * {@inheritdoc}
-   */
-  public function purgeFieldData(FieldDefinitionInterface $field_definition, $batch_size) {}
-
-  /**
-   * {@inheritdoc}
-   */
-  public function finalizePurge(FieldStorageDefinitionInterface $storage_definition) {}
-
-  /**
-   * {@inheritdoc}
-   */
-  public function onFieldDefinitionCreate(FieldDefinitionInterface $field_definition) {}
-
-  /**
-   * {@inheritdoc}
-   */
-  public function onFieldDefinitionUpdate(FieldDefinitionInterface $field_definition, FieldDefinitionInterface $original) {}
-
-  /**
-   * {@inheritdoc}
-   */
-  public function onFieldDefinitionDelete(FieldDefinitionInterface $field_definition) {}
-
-  /**
-   * {@inheritdoc}
-   */
-  public function onFieldStorageDefinitionCreate(FieldStorageDefinitionInterface $storage_definition) {}
-
-  /**
-   * {@inheritdoc}
-   */
-  public function onFieldStorageDefinitionUpdate(FieldStorageDefinitionInterface $storage_definition, FieldStorageDefinitionInterface $original) {}
-
-  /**
-   * {@inheritdoc}
-   */
-  public function onFieldStorageDefinitionDelete(FieldStorageDefinitionInterface $storage_definition) {}
-
-  /**
-   * {@inheritdoc}
-   */
-  public function createTranslation(ContentEntityInterface $entity, $langcode, array $values = []) {}
+  public function createTranslation(ContentEntityInterface $entity, $langcode, array $values = []) {
+    // @todo
+  }
 
 }
only in patch2:
unchanged:
--- a/core/modules/aggregator/src/FeedStorageInterface.php
+++ b/core/modules/aggregator/src/FeedStorageInterface.php
@@ -7,12 +7,12 @@
 
 namespace Drupal\aggregator;
 
-use Drupal\Core\Entity\EntityStorageInterface;
+use Drupal\Core\Entity\ContentEntityStorageInterface;
 
 /**
  * Defines an interface for aggregator feed entity storage classes.
  */
-interface FeedStorageInterface extends EntityStorageInterface {
+interface FeedStorageInterface extends ContentEntityStorageInterface {
 
   /**
    * Returns the fids of feeds that need to be refreshed.
only in patch2:
unchanged:
--- a/core/modules/aggregator/src/ItemStorageInterface.php
+++ b/core/modules/aggregator/src/ItemStorageInterface.php
@@ -7,12 +7,12 @@
 
 namespace Drupal\aggregator;
 
-use Drupal\Core\Entity\EntityStorageInterface;
+use Drupal\Core\Entity\ContentEntityStorageInterface;
 
 /**
  * Defines an interface for aggregator item entity storage classes.
  */
-interface ItemStorageInterface extends EntityStorageInterface {
+interface ItemStorageInterface extends ContentEntityStorageInterface {
 
   /**
    * Returns the count of the items in a feed.
only in patch2:
unchanged:
--- a/core/modules/comment/src/CommentStorageInterface.php
+++ b/core/modules/comment/src/CommentStorageInterface.php
@@ -8,13 +8,13 @@
 namespace Drupal\comment;
 
 use Drupal\Core\Entity\EntityInterface;
-use Drupal\Core\Entity\EntityStorageInterface;
+use Drupal\Core\Entity\ContentEntityStorageInterface;
 use Drupal\Core\Entity\FieldableEntityInterface;
 
 /**
  * Defines an interface for comment entity storage classes.
  */
-interface CommentStorageInterface extends EntityStorageInterface {
+interface CommentStorageInterface extends ContentEntityStorageInterface {
 
   /**
    * Gets the maximum encoded thread value for the top level comments.
only in patch2:
unchanged:
--- a/core/modules/file/src/FileStorageInterface.php
+++ b/core/modules/file/src/FileStorageInterface.php
@@ -7,12 +7,12 @@
 
 namespace Drupal\file;
 
-use Drupal\Core\Entity\EntityStorageInterface;
+use Drupal\Core\Entity\ContentEntityStorageInterface;
 
 /**
  * Defines an interface for file entity storage classes.
  */
-interface FileStorageInterface extends EntityStorageInterface {
+interface FileStorageInterface extends ContentEntityStorageInterface {
 
   /**
    * Determines total disk space used by a single user or the whole filesystem.
only in patch2:
unchanged:
--- a/core/modules/node/src/NodeStorageInterface.php
+++ b/core/modules/node/src/NodeStorageInterface.php
@@ -7,14 +7,14 @@
 
 namespace Drupal\node;
 
-use Drupal\Core\Entity\EntityStorageInterface;
+use Drupal\Core\Entity\ContentEntityStorageInterface;
 use Drupal\Core\Language\LanguageInterface;
 use Drupal\Core\Session\AccountInterface;
 
 /**
  * Defines an interface for node entity storage classes.
  */
-interface NodeStorageInterface extends EntityStorageInterface {
+interface NodeStorageInterface extends ContentEntityStorageInterface {
 
   /**
    * Gets a list of node revision IDs for a specific node.
only in patch2:
unchanged:
--- a/core/modules/taxonomy/src/TermStorageInterface.php
+++ b/core/modules/taxonomy/src/TermStorageInterface.php
@@ -8,12 +8,12 @@
 namespace Drupal\taxonomy;
 
 use Drupal\Core\Entity\EntityInterface;
-use Drupal\Core\Entity\EntityStorageInterface;
+use Drupal\Core\Entity\ContentEntityStorageInterface;
 
 /**
  * Defines an interface for taxonomy_term entity storage classes.
  */
-interface TermStorageInterface extends EntityStorageInterface {
+interface TermStorageInterface extends ContentEntityStorageInterface {
 
   /**
    * Removed reference to terms from term_hierarchy.
only in patch2:
unchanged:
--- a/core/modules/user/src/UserStorageInterface.php
+++ b/core/modules/user/src/UserStorageInterface.php
@@ -7,13 +7,13 @@
 
 namespace Drupal\user;
 
-use Drupal\Core\Entity\EntityStorageInterface;
+use Drupal\Core\Entity\ContentEntityStorageInterface;
 use Drupal\Core\Session\AccountInterface;
 
 /**
  * Defines an interface for user entity storage classes.
  */
-interface UserStorageInterface extends EntityStorageInterface{
+interface UserStorageInterface extends ContentEntityStorageInterface {
 
   /**
    * Update the last login timestamp of the user.