LibWeb+LibURL: Use URL paths directly for comparison

This matches the text of the spec a little more closely in many cases
and is also more efficient than serializing the URL path.

Userland/Libraries/LibURL/URL.h

@@ -150,6 +150,7 @@ public:
     void set_host(Host);
     void set_port(Optional<u16>);
     void set_paths(Vector<ByteString> const&);
+    Vector<String> const& paths() const { return m_data->paths; }
     void set_query(Optional<String> query) { m_data->query = move(query); }
     void set_fragment(Optional<String> fragment) { m_data->fragment = move(fragment); }
     void set_cannot_be_a_base_url(bool value) { m_data->cannot_be_a_base_url = value; }

Userland/Libraries/LibWeb/Fetch/Fetching/Fetching.cpp

@@ -799,7 +799,7 @@ WebIDL::ExceptionOr<JS::NonnullGCPtr<PendingResponse>> scheme_fetch(JS::Realm& r
         // a body.
         // NOTE: URLs such as "about:config" are handled during navigation and result in a network error in the context
         //       of fetching.
-        if (request->current_url().serialize_path() == "blank"sv) {
+        if (request->current_url().paths().size() == 1 && request->current_url().paths()[0] == "blank"sv) {
             auto response = Infrastructure::Response::create(vm);
             response->set_status_message(MUST(ByteBuffer::copy("OK"sv.bytes())));
 

Userland/Libraries/LibWeb/Fetch/Request.cpp

@@ -310,7 +310,8 @@ WebIDL::ExceptionOr<JS::NonnullGCPtr<Request>> Request::construct_impl(JS::Realm
             // - parsedReferrer’s origin is not same origin with origin
             // then set request’s referrer to "client".
             auto parsed_referrer_origin = DOMURL::url_origin(parsed_referrer);
-            if ((parsed_referrer.scheme() == "about"sv && parsed_referrer.serialize_path() == "client"sv) || !parsed_referrer_origin.is_same_origin(origin)) {
+            if ((parsed_referrer.scheme() == "about"sv && parsed_referrer.paths().size() == 1 && parsed_referrer.paths()[0] == "client"sv)
+                || !parsed_referrer_origin.is_same_origin(origin)) {
                 request->set_referrer(Infrastructure::Request::Referrer::Client);
             }
             // 4. Otherwise, set request’s referrer to parsedReferrer.

Userland/Libraries/LibWeb/HTML/BrowsingContext.cpp

@@ -40,7 +40,7 @@ bool url_matches_about_blank(URL::URL const& url)
 {
     // A URL matches about:blank if its scheme is "about", its path contains a single string "blank", its username and password are the empty string, and its host is null.
     return url.scheme() == "about"sv
-        && url.serialize_path() == "blank"sv
+        && url.paths().size() == 1 && url.paths()[0] == "blank"sv
         && url.username().is_empty()
         && url.password().is_empty()
         && url.host().has<Empty>();
@@ -51,7 +51,7 @@ bool url_matches_about_srcdoc(URL::URL const& url)
 {
     // A URL matches about:srcdoc if its scheme is "about", its path contains a single string "srcdoc", its query is null, its username and password are the empty string, and its host is null.
     return url.scheme() == "about"sv
-        && url.serialize_path() == "srcdoc"sv
+        && url.paths().size() == 1 && url.paths()[0] == "srcdoc"sv
         && !url.query().has_value()
         && url.username().is_empty()
         && url.password().is_empty()

Userland/Libraries/LibWeb/HTML/History.cpp

@@ -148,17 +148,13 @@ bool can_have_its_url_rewritten(DOM::Document const& document, URL::URL const& t
 
     // 4. If targetURL's scheme is "file", and targetURL and documentURL differ in their path component,
     //    then return false. (Differences in query and fragment are allowed for file: URLs.)
-    // FIXME: Don't create temporary strings to compare paths
+    bool path_components_match = target_url.paths() == document_url.paths();
-    auto target_url_path = target_url.serialize_path();
+    if (target_url.scheme() == "file"sv && !path_components_match)
-    auto document_url_path = document_url.serialize_path();
-    if (target_url.scheme() == "file"sv
-        && target_url_path != document_url_path)
         return false;
 
     // 5. If targetURL and documentURL differ in their path component or query components, then return false.
     //    (Only differences in fragment are allowed for other types of URLs.)
-    if (target_url_path != document_url_path
+    if (!path_components_match || target_url.query() != document_url.query())
-        || target_url.query() != document_url.query())
         return false;
 
     // 6. Return true.