TranslationHelper not working for EditorialContentEntityBase entities

In version 1 of IEF, TranslationHelper worked for storage entities. That's because it didn't provide the conditional logic that this patch corrects.

While the patch addresses the specific issue it found for TranslationHelper, there is need to fix more of inline entity form in order for a content creator / editing to manage content that uses both inline entity form and storage entities.

The same issue and fix that this issue is talking about was reported in 🐛 Unable to update micro-content entities via Inline Entity Form Active . I believe we need the same kind of fix there.

When thinking about where to put that logic, I was wondering if expanding this patch to include the additional fix would be good.

Should I expand the scope of this issue / patch?

After this change there is only more additional use of ContentEntityTypeInterface but it appears to be in logic that hides the revision log for revisionable content types:

EntityInlineForm::entityForm line 211

// Hide the log message field for revisionable entity types. It cannot be
    // disabled in UI and does not make sense in inline entity form context.
    if (($this->entityType instanceof ContentEntityTypeInterface)) {
      if ($log_message_key = $this->entityType->getRevisionMetadataKey('revision_log_message')) {
        // Safely restrict access. Entity type cacheability already set.
        RenderArray::alter($entity_form[$log_message_key])->restrictAccess(FALSE, NULL);
      }
    }

Should we discuss if this should be modified to target ContentEntityInterface instead?

Would be great to hear more from @matthieuscarseta about current state of the MR