Enable first party for cookies check on Linux

https://bugs.webkit.org/show_bug.cgi?id=247693
rdar://102154645

Reviewed by Carlos Garcia Campos.

I think 256488@main resolved the problem and now the check can be done on all platforms.

* Source/WebKit/NetworkProcess/NetworkConnectionToWebProcess.cpp:
(WebKit::NetworkConnectionToWebProcess::scheduleResourceLoad):

Canonical link: https://commits.webkit.org/258186@main

Source/WebKit/NetworkProcess/NetworkConnectionToWebProcess.cpp

@@ -550,11 +550,7 @@ std::unique_ptr<ServiceWorkerFetchTask> NetworkConnectionToWebProcess::createFet
 
 void NetworkConnectionToWebProcess::scheduleResourceLoad(NetworkResourceLoadParameters&& loadParameters, std::optional<NetworkResourceLoadIdentifier> existingLoaderToResume)
 {
-    // FIXME: This shouldn't be different on different platforms.
-    // It may be related to the difference in networkProcessForSession.
-#if !PLATFORM(GTK) && !PLATFORM(WPE)
     NETWORK_PROCESS_MESSAGE_CHECK(m_networkProcess->allowsFirstPartyForCookies(m_webProcessIdentifier, loadParameters.request.firstPartyForCookies()));
-#endif
 
     CONNECTION_RELEASE_LOG(Loading, "scheduleResourceLoad: (parentPID=%d, pageProxyID=%" PRIu64 ", webPageID=%" PRIu64 ", frameID=%" PRIu64 ", resourceID=%" PRIu64 ", existingLoaderToResume=%" PRIu64 ")", loadParameters.parentPID, loadParameters.webPageProxyID.toUInt64(), loadParameters.webPageID.toUInt64(), loadParameters.webFrameID.object().toUInt64(), loadParameters.identifier.toUInt64(), valueOrDefault(existingLoaderToResume).toUInt64());