AK+Everywhere: Change URL::path() to serialize_path()

This now defaults to serializing the path with percent decoded segments
(which is what all callers expect), but has an option not to. This fixes
`file://` URLs with spaces in their paths.

The name has been changed to serialize_path() path to make it more clear
that this method will generate a new string each call (except for the
cannot_be_a_base_url() case). A few callers have then been updated to
avoid repeatedly calling this function.

Userland/Libraries/LibWeb/HTML/BrowsingContext.cpp

@@ -39,7 +39,7 @@ static bool url_matches_about_blank(AK::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.path() == "blank"sv
+        && url.serialize_path() == "blank"sv
         && url.username().is_empty()
         && url.password().is_empty()
         && url.host().is_null();

Userland/Libraries/LibWeb/HTML/BrowsingContextContainer.cpp

@@ -121,7 +121,7 @@ static bool url_matches_about_blank(AK::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.path() == "blank"sv
+        && url.serialize_path() == "blank"sv
         && url.username().is_empty()
         && url.password().is_empty()
         && url.host().is_null();

Userland/Libraries/LibWeb/HTML/HTMLHyperlinkElementUtils.cpp

@@ -293,7 +293,7 @@ DeprecatedString HTMLHyperlinkElementUtils::pathname() const
     // 4. If url's cannot-be-a-base-URL is true, then return url's path[0].
     // 5. If url's path is empty, then return the empty string.
     // 6. Return "/", followed by the strings in url's path (including empty strings), separated from each other by "/".
-    return m_url->path();
+    return m_url->serialize_path();
 }
 
 // https://html.spec.whatwg.org/multipage/links.html#dom-hyperlink-pathname

Userland/Libraries/LibWeb/HTML/Location.cpp

@@ -233,7 +233,7 @@ WebIDL::ExceptionOr<String> Location::pathname() const
         return WebIDL::SecurityError::create(realm(), "Location's relevant document is not same origin-domain with the entry settings object's origin"sv);
 
     // 2. Return the result of URL path serializing this Location object's url.
-    return TRY_OR_THROW_OOM(vm, String::from_deprecated_string(url().path()));
+    return TRY_OR_THROW_OOM(vm, String::from_deprecated_string(url().serialize_path()));
 }
 
 WebIDL::ExceptionOr<void> Location::set_pathname(String const&)

Userland/Libraries/LibWeb/HTML/WorkerLocation.cpp

@@ -92,7 +92,7 @@ WebIDL::ExceptionOr<String> WorkerLocation::pathname() const
 {
     auto& vm = realm().vm();
     // The pathname getter steps are to return the result of URL path serializing this's WorkerGlobalScope object's url.
-    return TRY_OR_THROW_OOM(vm, String::from_deprecated_string(m_global_scope->url().path()));
+    return TRY_OR_THROW_OOM(vm, String::from_deprecated_string(m_global_scope->url().serialize_path()));
 }
 
 // https://html.spec.whatwg.org/multipage/workers.html#dom-workerlocation-search