LibWeb: Add the IDL for the GenericTransformStream mixin

Author: https://github.com/trflynn89
Commit: 35ba7c7e00
Pull-request: https://github.com/LadybirdBrowser/ladybird/pull/2370

Libraries/LibWeb/Streams/GenericTransformStream.h

@@ -0,0 +1,30 @@
+/*
+ * Copyright (c) 2024, Tim Flynn <trflynn89@ladybird.org>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#pragma once
+
+#include <LibGC/Cell.h>
+#include <LibGC/Ptr.h>
+#include <LibWeb/Forward.h>
+
+namespace Web::Streams {
+
+class GenericTransformStreamMixin {
+public:
+    virtual ~GenericTransformStreamMixin();
+
+    GC::Ref<ReadableStream> readable();
+    GC::Ref<WritableStream> writable();
+
+protected:
+    explicit GenericTransformStreamMixin(GC::Ref<TransformStream>);
+    void visit_edges(GC::Cell::Visitor&);
+
+    // https://streams.spec.whatwg.org/#generictransformstream-transform
+    GC::Ref<TransformStream> m_transform;
+};
+
+}