LibWeb: Port EventLoop::spin_XXX to HeapFunction

Author: https://github.com/shannonbooth
Commit: 1c18b900e2
Pull-request: https://github.com/LadybirdBrowser/ladybird/pull/2062
Reviewed-by: https://github.com/kalenikaliaksandr ✅

Userland/Libraries/LibWeb/HTML/Scripting/Fetching.cpp

@@ -505,9 +505,9 @@ WebIDL::ExceptionOr<JS::NonnullGCPtr<ClassicScript>> fetch_a_classic_worker_impo
 
     // 5. Pause until response is not null.
     auto& event_loop = settings_object.responsible_event_loop();
-    event_loop.spin_until([&]() {
+    event_loop.spin_until(JS::create_heap_function(vm.heap(), [&]() -> bool {
         return response;
-    });
+    }));
 
     // 6. Set response to response's unsafe response.
     response = response->unsafe_response();