1 files changed, 3 insertions, 0 deletions
diff --git a/components/shared/constellation/message_port.rs b/components/shared/constellation/message_port.rs
index 8fe40418004..bb2929353af 100644
--- a/components/shared/constellation/message_port.rs
+++ b/components/shared/constellation/message_port.rs
@@ -233,6 +233,8 @@ pub enum Transferrable {
     MessagePort,
     /// The `ReadableStream` interface.
     ReadableStream,
+    /// The `WritableStream` interface.
+    WritableStream,
 }
 
 impl StructuredSerializedData {
@@ -243,6 +245,7 @@ impl StructuredSerializedData {
         match val {
             Transferrable::MessagePort => is_field_empty(&self.ports),
             Transferrable::ReadableStream => is_field_empty(&self.ports),
+            Transferrable::WritableStream => is_field_empty(&self.ports),
         }
     }