LibWeb: Implement 'fetch timing info' struct

Userland/Libraries/LibWeb/Fetch/Infrastructure/FetchTimingInfo.cpp

@@ -0,0 +1,37 @@
+/*
+ * Copyright (c) 2022, Linus Groh <linusg@serenityos.org>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include <LibJS/Heap/Heap.h>
+#include <LibJS/Runtime/VM.h>
+#include <LibWeb/Fetch/Infrastructure/FetchTimingInfo.h>
+
+namespace Web::Fetch::Infrastructure {
+
+FetchTimingInfo::FetchTimingInfo() = default;
+
+JS::NonnullGCPtr<FetchTimingInfo> FetchTimingInfo::create(JS::VM& vm)
+{
+    return { *vm.heap().allocate_without_realm<FetchTimingInfo>() };
+}
+
+void FetchTimingInfo::visit_edges(JS::Cell::Visitor& visitor)
+{
+    Base::visit_edges(visitor);
+    visitor.visit(m_final_connection_timing_info);
+}
+
+// https://fetch.spec.whatwg.org/#create-an-opaque-timing-info
+JS::NonnullGCPtr<FetchTimingInfo> create_opaque_timing_info(JS::VM& vm, FetchTimingInfo const& timing_info)
+{
+    // To create an opaque timing info, given a fetch timing info timingInfo, return a new fetch timing info whose
+    // start time and post-redirect start time are timingInfo’s start time.
+    auto new_timing_info = FetchTimingInfo::create(vm);
+    new_timing_info->set_start_time(timing_info.start_time());
+    new_timing_info->set_post_redirect_start_time(timing_info.start_time());
+    return new_timing_info;
+}
+
+}