8 files declare their use of SqlEntityStorageInterface

content_translation.install in core/modules/content_translation/content_translation.install
Installation functions for Content Translation module.
EntityViewsData.php in core/modules/views/src/EntityViewsData.php
KernelTestBase.php in core/modules/simpletest/src/KernelTestBase.php
KernelTestBase.php in core/tests/Drupal/KernelTests/KernelTestBase.php
media.install in core/modules/media/media.install
Install, uninstall and update hooks for Media module.
Tables.php in core/lib/Drupal/Core/Entity/Query/Sql/Tables.php
taxonomy.install in core/modules/taxonomy/taxonomy.install
Install, update and uninstall functions for the taxonomy module.
views_test_query_access.module in core/modules/views/tests/modules/views_test_query_access/views_test_query_access.module
Module to test entity query access in Views.

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