LibURL: Define Origin methods depending on URL::Parser out of line

This is also in an effort towards resolving a future circular dependency
between Origin.h and URL.h

Userland/Libraries/LibURL/Origin.cpp

@@ -0,0 +1,50 @@
+/*
+ * Copyright (c) 2024, Shannon Booth <shannon@serenityos.org>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include <LibURL/Origin.h>
+#include <LibURL/Parser.h>
+
+namespace URL {
+
+// https://html.spec.whatwg.org/multipage/origin.html#ascii-serialisation-of-an-origin
+ByteString Origin::serialize() const
+{
+    // 1. If origin is an opaque origin, then return "null"
+    if (is_opaque())
+        return "null";
+
+    // 2. Otherwise, let result be origin's scheme.
+    StringBuilder result;
+    result.append(scheme());
+
+    // 3. Append "://" to result.
+    result.append("://"sv);
+
+    // 4. Append origin's host, serialized, to result.
+    result.append(Parser::serialize_host(host()).release_value_but_fixme_should_propagate_errors().to_byte_string());
+
+    // 5. If origin's port is non-null, append a U+003A COLON character (:), and origin's port, serialized, to result.
+    if (port() != 0) {
+        result.append(':');
+        result.append(ByteString::number(port()));
+    }
+    // 6. Return result
+    return result.to_byte_string();
+}
+
+}
+
+namespace AK {
+
+unsigned Traits<URL::Origin>::hash(URL::Origin const& origin)
+{
+    auto hash_without_host = pair_int_hash(origin.scheme().hash(), origin.port());
+    if (origin.host().has<Empty>())
+        return hash_without_host;
+    return pair_int_hash(hash_without_host, URL::Parser::serialize_host(origin.host()).release_value_but_fixme_should_propagate_errors().hash());
+}
+
+} // namespace AK