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@Nuranto can you include a revert of the broken code here? 632f253

Actually, looking at this code, I wonder if we shouldn't take the opportunity to do a more thorough refactoring. This PR is a conveninent quick fix for the issue, but there's more to do :

The AddComment controller should use the OrderService::addComment service, and the state/status check that I added here should be done in the Order::addStatusHistory class. We will then need to revise the tests accordingly....

It's a too big task for me, especially without being sure that the PR will be approved, I think it would be worth asking for the opinion of the Magento architects.

What do you think ?