pub fn construct_message_channel(_args: &[Value]) -> Result<Value, String>Expand description
new MessageChannel() → { port1, port2 }, two MessagePort objects linked
so that port1.postMessage(v) is delivered to port2 (and vice versa). Both
ports live on the calling thread and share its heap; messages are cloned
through the JSON subset (serialize/deserialize) so a posted object is a
copy, not a shared reference — matching structured clone’s copy semantics.
Requires the parent to wire MessageChannel construction (see the report).