Moderation state is not copied

This patch may not be the best solution but it works for me. Happy to discuss.

Regards Rory

I am not sure now about the owner reference - I need to test but it may be the module's behaviour anyway! I will test and adjust my patch accordingly when I get a moment! It occurs to me that the owner base field is probably not an entity reference class!

The default behaviour of this code is to blank a field if there is nothing in the jsonapi.

This happens with uid and the bundle field of a media entity. In the case of uid (which is not mandatory) this means it gets anonymous. In the case of the media entity bundle field this means that it causes a crash because bundle is a required field.

So I have taken out the code to force the uid, leaving it as anonymous and put in a test to not put empty data into a mandatory field but instead leave it unchanged.

I have now found that this patch does not work when running in the cron. It comes up with an error:
Error: Call to a member function isRequired() on null in Drupal\entity_share_client\Plugin\EntityShareClient\Processor\EntityReference->processEntity() (line 194 of modules/contrib/entity_share/modules/entity_share_client/src/Plugin/EntityShareClient/Processor/EntityReference.php).

Also it occurs to me that these latest changes to my patch are possibly fixing bugs in the core. I did a quick search and could not find an existing issue.

Anyway, it seems I have opened a can of worms with this approach so I am going to try to solve the problem that I reported with a new specific Processor plugin to specifically manage moderation state.

OK, now I have a patch creating a new, optional processor. It checks to ensure the following:

1. The workbench moderation module is installed
2. The entity is moderated
3. The data from the source contains a moderation state
4. This moderation state exists in the client site

As this is a completely different approach, I have not supplied an interdiff.