9 files declare their use of DatabaseStorageControllerNG

CommentStorageController.php in drupal/core/modules/comment/lib/Drupal/comment/CommentStorageController.php
Definition of Drupal\comment\CommentStorageController.
CustomBlockStorageController.php in drupal/core/modules/block/custom_block/lib/Drupal/custom_block/CustomBlockStorageController.php
Contains \Drupal\custom_block\CustomBlockStorageController.
EntityTestStorageController.php in drupal/core/modules/system/tests/modules/entity_test/lib/Drupal/entity_test/EntityTestStorageController.php
Definition of Drupal\entity_test\EntityTestStorageController.
EntityTranslationTestBase.php in drupal/core/modules/translation_entity/lib/Drupal/translation_entity/Tests/EntityTranslationTestBase.php
Contains \Drupal\entity\Tests\EntityTranslationTestBase.
FeedStorageController.php in drupal/core/modules/aggregator/lib/Drupal/aggregator/FeedStorageController.php
Contains \Drupal\aggregator\FeedStorageController.
ItemStorageController.php in drupal/core/modules/aggregator/lib/Drupal/aggregator/ItemStorageController.php
Contains \Drupal\aggregator\ItemStorageController.
NodeStorageController.php in drupal/core/modules/node/lib/Drupal/node/NodeStorageController.php
Definition of Drupal\node\NodeStorageController.
TermStorageController.php in drupal/core/modules/taxonomy/lib/Drupal/taxonomy/TermStorageController.php
Definition of Drupal\taxonomy\TermStorageController.
UserStorageController.php in drupal/core/modules/user/lib/Drupal/user/UserStorageController.php
Definition of Drupal\user\UserStorageController.