Issue #3253104 by jsacksick: Ensure a price is resolved before setting the unit price on refresh.

        $order_item->setTitle($purchased_entity->getOrderItemTitle());

        if (!$order_item->isUnitPriceOverridden()) {

          $unit_price = $this->chainPriceResolver->resolve($purchased_entity, $order_item->getQuantity(), $context);

          $order_item->setUnitPrice($unit_price);

          $unit_price ? $order_item->setUnitPrice($unit_price) : $order_item->set('unit_price', NULL);

        }

      }

      // If the order refresh is running during order preSave(),