diff --git a/core/modules/block/custom_block/custom_block.install b/core/modules/block/custom_block/custom_block.install
index 6c27dd9..acc374a 100644
--- a/core/modules/block/custom_block/custom_block.install
+++ b/core/modules/block/custom_block/custom_block.install
@@ -124,80 +124,6 @@ function custom_block_schema() {
   return $schema;
 }
 
-/**
- * Implements hook_schema_0().
- */
-function custom_block_schema_0() {
-  $schema = array();
-  $schema['custom_block'] = array(
-    'description' => 'Stores contents of custom-made blocks.',
-    'fields' => array(
-      'id' => array(
-        'type' => 'serial',
-        'unsigned' => TRUE,
-        'not null' => TRUE,
-        'description' => "The block's {custom_block}.id.",
-      ),
-      'uuid' => array(
-        'description' => 'Unique Key: Universally unique identifier for this entity.',
-        'type' => 'varchar',
-        'length' => 128,
-        'not null' => FALSE,
-      ),
-      'info' => array(
-        'type' => 'varchar',
-        'length' => 128,
-        'not null' => TRUE,
-        'default' => '',
-        'description' => 'Block description.',
-      ),
-      // Defaults to NULL in order to avoid a brief period of potential
-      // deadlocks on the index.
-      'revision_id' => array(
-        'description' => 'The current {block_custom_revision}.revision_id version identifier.',
-        'type' => 'int',
-        'unsigned' => TRUE,
-        'not null' => FALSE,
-        'default' => NULL,
-      ),
-      'type' => array(
-        'description' => 'The type of this custom block.',
-        'type' => 'varchar',
-        'length' => EntityTypeInterface::BUNDLE_MAX_LENGTH,
-        'not null' => TRUE,
-        'default' => '',
-      ),
-      'changed' => array(
-        'description' => 'The Unix timestamp when the custom block was most recently saved.',
-        'type' => 'int',
-        'not null' => TRUE,
-        'default' => 0,
-      ),
-      'langcode' => array(
-        'description' => 'The {language}.langcode of this node.',
-        'type' => 'varchar',
-        'length' => 12,
-        'not null' => TRUE,
-        'default' => '',
-      ),
-    ),
-    'primary key' => array('id'),
-    'indexes' => array(
-      'block_custom_type' => array('type'),
-    ),
-    'unique keys' => array(
-      'revision_id' => array('revision_id'),
-      'uuid' => array('uuid'),
-      'info' => array('info'),
-    ),
-    'foreign keys' => array(
-      'custom_block_revision' => array(
-        'table' => 'custom_block_revision',
-        'columns' => array('revision_id' => 'revision_id'),
-      ),
-    ),
-  );
-
   $schema['custom_block_revision'] = array(
     'description' => 'Stores contents of custom-made blocks.',
     'fields' => array(