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/script/dom/bindings/structuredclone.rs

@@ -41,6 +41,7 @@ use crate::dom::dompoint::DOMPoint;
 use crate::dom::dompointreadonly::DOMPointReadOnly;
 use crate::dom::globalscope::GlobalScope;
 use crate::dom::messageport::MessagePort;
+use crate::dom::readablestream::ReadableStream;
 use crate::realms::{AlreadyInRealm, InRealm, enter_realm};
 use crate::script_runtime::{CanGc, JSContext as SafeJSContext};
 
@@ -57,6 +58,7 @@ pub(super) enum StructuredCloneTags {
     Principals = 0xFFFF8003,
     DomPointReadOnly = 0xFFFF8004,
     DomPoint = 0xFFFF8005,
+    ReadableStream = 0xFFFF8006,
     Max = 0xFFFFFFFF,
 }
 
@@ -74,6 +76,7 @@ impl From<TransferrableInterface> for StructuredCloneTags {
     fn from(v: TransferrableInterface) -> Self {
         match v {
             TransferrableInterface::MessagePort => StructuredCloneTags::MessagePort,
+            TransferrableInterface::ReadableStream => StructuredCloneTags::ReadableStream,
         }
     }
 }
@@ -250,6 +253,7 @@ fn receiver_for_type(
 ) -> fn(&GlobalScope, &mut StructuredDataReader, u64, RawMutableHandleObject) -> Result<(), ()> {
     match val {
         TransferrableInterface::MessagePort => receive_object::<MessagePort>,
+        TransferrableInterface::ReadableStream => receive_object::<ReadableStream>,
     }
 }
 
@@ -375,6 +379,7 @@ type TransferOperation = unsafe fn(
 fn transfer_for_type(val: TransferrableInterface) -> TransferOperation {
     match val {
         TransferrableInterface::MessagePort => try_transfer::<MessagePort>,
+        TransferrableInterface::ReadableStream => try_transfer::<ReadableStream>,
     }
 }
 
@@ -421,6 +426,7 @@ unsafe fn can_transfer_for_type(
     }
     match transferable {
         TransferrableInterface::MessagePort => can_transfer::<MessagePort>(obj, cx),
+        TransferrableInterface::ReadableStream => can_transfer::<ReadableStream>(obj, cx),
     }
 }
 
@@ -507,6 +513,7 @@ pub(crate) struct StructuredDataReader {
     pub(crate) blob_impls: Option<HashMap<BlobId, BlobImpl>>,
     /// A map of serialized points.
     pub(crate) points: Option<HashMap<DomPointId, DomPoint>>,
+    pub(crate) readable_streams: Option<Vec<DomRoot<ReadableStream>>>,
 }
 
 /// A data holder for transferred and serialized objects.
@@ -597,6 +604,7 @@ pub(crate) fn read(
         blob_impls: data.blobs.take(),
         points: data.points.take(),
         errors: DOMErrorRecord { message: None },
+        readable_streams: None,
     };
     let sc_reader_ptr = &mut sc_reader as *mut _;
     unsafe {