Transfer ReadableStream (#36181)

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Add transfer support to ReadableStream. Part of
https://github.com/servo/servo/issues/34676

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---------

Signed-off-by: gterzian <2792687+gterzian@users.noreply.github.com>

components/shared/constellation/message_port.rs

@@ -224,6 +224,8 @@ impl Serializable {
 pub enum Transferrable {
     /// The `MessagePort` interface.
     MessagePort,
+    /// The `ReadableStream` interface.
+    ReadableStream,
 }
 
 impl StructuredSerializedData {
@@ -233,6 +235,7 @@ impl StructuredSerializedData {
         }
         match val {
             Transferrable::MessagePort => is_field_empty(&self.ports),
+            Transferrable::ReadableStream => is_field_empty(&self.ports),
         }
     }