sharedArrayBuffer
{SharedArrayBuffer}
This method is called when the serializer is going to serialize a
SharedArrayBuffer
object. It must return an unsigned 32-bit integer ID for
the object, using the same ID if this SharedArrayBuffer
has already been
serialized. When deserializing, this ID will be passed to
[deserializer.transferArrayBuffer()
][].
If the object cannot be serialized, an exception should be thrown.
This method is not present on the Serializer
class itself but can be provided
by subclasses.