EntityResource only sets entity cache tags on response; cache tags for entity reference fields missing

Seems to be a lack in the Drupal rest EntityResource code.
when using entity Drupal RESTful Web Services the X-Drupal-Cache-Tags header does not include the related entities.

Examples:

www.example.com/sv/start returns
"X-Drupal-Cache-Tags: block_content:1 block_content_view block_view config:block.block.preview config:block.block.seven_breadcrumbs config:block.block.seven_content config:block.block.seven_help config:block.block.seven_local_actions config:block.block.seven_login config:block.block.seven_messages config:block.block.seven_page_title config:block.block.seven_primary_local_tasks config:block.block.seven_secondary_local_tasks config:block_list config:filter.format.full_html config:system.site config:user.role.anonymous node:6816 node:6841 node:6865 node:6867 node:6869 node:6927 node:6928 node:7428 node:9370 node:9449 node:9452 node:9631 node:9660 node_view rendered user:0 user:1"

www.example.com/sv/start?_format=json returns
"X-Drupal-Cache-Tags: config:rest.settings config:user.role.anonymous node:9370”

If I add the following to "core/modules/rest/src/Plugin/rest/resource/EntityResource.php", method get, then all related entities are in the X-Drupal-Cache-Tags:

$entcb = function($refEnts, $resp) use (&$entcb) {
   foreach($refEnts as $refEnt) {
     $entcb($refEnt->referencedEntities(), $resp);
     $resp->addCacheableDependency($refEnt);
   }
};
$entcb($entity->referencedEntities(), $response);

www.example.com/sv/start?_format=json returns
X-Drupal-Cache-Tags: config:node.type.billboard config:node.type.static_frontpage config:node.type.teaser config:node.type.teaser_html config:rest.settings config:taxonomy.vocabulary.main config:taxonomy.vocabulary.selfservice config:taxonomy.vocabulary.teasers config:user.role.administrator config:user.role.anonymous config:user.role.editor_club_ config:user.role.editor_global_ file:264 file:3139 file:3411 file:3614 file:4019 file:4219 file:4245 file:4370 file:4793 file:5413 node:6816 node:6841 node:6865 node:6867 node:6869 node:6927 node:6928 node:7428 node:9370 node:9449 node:9452 node:9631 node:9660 taxonomy_term:280 taxonomy_term:281 taxonomy_term:282 taxonomy_term:283 taxonomy_term:284 user:0 user:1 user:19 user:28 user:3 user:6 user:7 user:8

I've added a patch file of my change if you'll like to add it.