Mixed type handler throws error when data is array

[ReservedDeveloper]

When using the @Serializer\Type("Mixed") notation, the serializer will throw an error if the provided data is an array. This is due to the is_object() check occurring in the SerializationContext::isVisiting() method. The reason this check is performed is because Type("Mixed") is interpreted as a custom object type.

[ReservedDeveloper]

One theoretical quick-fix approach for this would be to cast any array data set to a Mixed type field (ex: Response::$data) to object. Not pretty, but should resolve the issue.