Machine name not set when using sub queue as an entity reference

I thought I fixed this in #2946694: 'name' empty when using inline_entity_form widget but apparently IEF only works with the fields defined in the entity form display, so we really need the machine name widget from #2685749: Add a 'machine_name' widget for string field types with a UniqueField constraint.

Until that issue gets committed to core, we'll have to copy its code :)

Oops, here's the patch that was committed.

And a followup patch to fix things :)

After more testing, things are still not working properly with the new machine name widget, so reverted both patches for now and released beta5.

This is an issue also reported in #3478759: Entityqueue entity fails to import, which uses Default Content.

I am also getting this error when attempting to import and entity_subqueue via Default Content:

In ExceptionHandler.php line 45:

SQLSTATE[HY000]: General error: 1364 Field 'name' doesn't have a default value: INSERT INTO "entity_subqueue" ("revision_id", "queue", "uuid", "langcode") VALUES (:db_insert_placeholder_0, :db_insert_placeholder_1, :db_insert_placeholder_2, :db_insert_placeholder_3); Array 
(
      [:db_insert_placeholder_0] =>
      [:db_insert_placeholder_1] => my_entity_subqueue
      [:db_insert_placeholder_2] => c3655edc-a41b-42bd-bf82-5cbc92268c67
      [:db_insert_placeholder_3] => en
  )

In StatementWrapperIterator.php line 113:

SQLSTATE[HY000]: General error: 1364 Field 'name' doesn't have a default value