This reduces the boilerplate necessary for adding new
serializable/transferable interfaces to the structured cloning code. We
always need to root the deserialized objects when performing a read
operation, but we don't actually need the concrete object types in the
majority of cases. By storing a list of rooted JS object values, we can
push generic reflector objects into it, and extract the types we need
(MessagePort) at the very end.
Testing: Existing WPT structured cloning tests will provide coverage.
Signed-off-by: Josh Matthews <josh@joshmatthews.net>
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