DefaultSerializationProxy
final class DefaultSerializationProxy[A](factory: Factory[A, Any], coll: Iterable[A]) extends Serializable
The default serialization proxy for collection implementations.
This class is final and requires an extra Factory object rather than leaving the details of creating a Builder
to an abstract method that could be implemented by a subclass. This is necessary because the factory is needed
for deserializing this class's private state, which happens before any subclass fields would be deserialized. Any
additional state required to create the proper Builder needs to be captured by the factory.