Let "Migrate" import behaviour driven properties

@derhasi, thank you for the patch. I am not sure that adding code to the behavior is the best way to handle the problem. I have not used migrate, so I do not know how it works, but would deactivating the behavior work?

I added a couple of function to the EntityType class to make that easier:

 //deactive the behavior of the 'changed' property
    $entity_type = EntityType::loadByName($entity_type);
    $entity_type->removeBehavior('changed');
    $entity_type->save();

    //do stuff with entities of $entity_type while the changed behavior is deactivated
    
    //reactivate the 'changed' behavior in the 'changed' property
    $entity_type->changeBehavior('changed', 'changed');
    $entity_type->save();

would this approach work?

Do you think the solution presented by @acrazyanimal here #1600838: Author and Created behaviours override previously set values would solve the problem? I think the solution in the other issue is a little bit more general than an if statement targeted to the migrate module. Let me know, otherwise I will push your path through until a better solution can be implemented.

The patch in #1600838: Author and Created behaviours override previously set values has been committed and should resolve this issue as well. Marking as fixed.

Gotcha! Right, I had assumed that 'changed' would always be the date that it was changed and thus we didn't need to worry about this case. However, I did not consider imports/migration on entity creation. Cool I'll see what I can do.

Try this patch out.