IDL: Add support for [Unscopeable] on attributes and methods

Source/bindings/templates/partial_interface.h

Index: Source/bindings/templates/partial_interface.h
diff --git a/Source/bindings/templates/partial_interface.h b/Source/bindings/templates/partial_interface.h
index 160a3936ee6a97debd90b6bcd178a43b28478fc8..b85998950a8b3e41cca5b1e93f8b2ce95655aec3 100644
--- a/Source/bindings/templates/partial_interface.h
+++ b/Source/bindings/templates/partial_interface.h
@@ -29,7 +29,7 @@ public:
     {% endif %}
     {% endfor %}
     {# Custom internal fields #}
-    static void installConditionallyEnabledMethods(v8::Local<v8::Object>, v8::Isolate*);
+    static void preparePrototypeObject(v8::Isolate*, v8::Local<v8::Object>);
 private:
     static void install{{v8_class}}Template(v8::Local<v8::FunctionTemplate>, v8::Isolate*);
 };