Remove NetworkResourceLoader::m_resultingClientIdentifier

https://bugs.webkit.org/show_bug.cgi?id=256357
rdar://problem/108937686

Reviewed by Alex Christensen.

We no longer need NetworkResourceLoader::m_resultingClientIdentifier:
- We are consistently storing the identifier inside NetworkResourceLoader parameters.
- On same origin redirections, we reuse the same identifier and are doing so even if transferring to another web process.
- On cross origin redirections, we should not reuse the same identifier and use a different NetworkResourceLoader.

* Source/WebKit/NetworkProcess/NetworkResourceLoader.h:
* Source/WebKit/NetworkProcess/ServiceWorker/ServiceWorkerFetchTask.cpp:
(WebKit::ServiceWorkerFetchTask::startFetch):
* Source/WebKit/NetworkProcess/ServiceWorker/WebSWServerConnection.cpp:
(WebKit::WebSWServerConnection::createFetchTask):

Canonical link: https://commits.webkit.org/264461@main

Source/WebKit/NetworkProcess/NetworkResourceLoader.h

@@ -160,8 +160,6 @@ class NetworkResourceLoader final
 #if ENABLE(SERVICE_WORKER)
     void startWithServiceWorker();
     void serviceWorkerDidNotHandle(ServiceWorkerFetchTask*);
-    void setResultingClientIdentifier(String&& identifier) { m_resultingClientIdentifier = WTFMove(identifier); }
-    const String& resultingClientIdentifier() const { return m_resultingClientIdentifier; }
     void setServiceWorkerRegistration(WebCore::SWServerRegistration& serviceWorkerRegistration) { m_serviceWorkerRegistration = serviceWorkerRegistration; }
     void setWorkerStart(MonotonicTime);
     MonotonicTime workerStart() const { return m_workerStart; }
@@ -314,7 +312,6 @@ class NetworkResourceLoader final
     std::optional<NetworkActivityTracker> m_networkActivityTracker;
 #if ENABLE(SERVICE_WORKER)
     std::unique_ptr<ServiceWorkerFetchTask> m_serviceWorkerFetchTask;
-    String m_resultingClientIdentifier;
     WeakPtr<WebCore::SWServerRegistration> m_serviceWorkerRegistration;
     MonotonicTime m_workerStart;
 #endif

Source/WebKit/NetworkProcess/ServiceWorker/ServiceWorkerFetchTask.cpp

@@ -174,8 +174,11 @@ void ServiceWorkerFetchTask::startFetch()
         if (auto identifier = m_loader.parameters().options.clientIdentifier)
             clientIdentifier = identifier->toString();
     }
+    String resultingClientIdentifier;
+    if (auto& identifier = m_loader.parameters().options.resultingClientIdentifier)
+        resultingClientIdentifier = identifier->toString();
 
-    bool isSent = sendToServiceWorker(Messages::WebSWContextManagerConnection::StartFetch { m_serverConnectionIdentifier, m_serviceWorkerIdentifier, m_fetchIdentifier, request, options, IPC::FormDataReference { m_currentRequest.httpBody() }, referrer, m_preloader && m_preloader->isServiceWorkerNavigationPreloadEnabled(), clientIdentifier, m_loader.resultingClientIdentifier() });
+    bool isSent = sendToServiceWorker(Messages::WebSWContextManagerConnection::StartFetch { m_serverConnectionIdentifier, m_serviceWorkerIdentifier, m_fetchIdentifier, request, options, IPC::FormDataReference { m_currentRequest.httpBody() }, referrer, m_preloader && m_preloader->isServiceWorkerNavigationPreloadEnabled(), clientIdentifier, resultingClientIdentifier });
     ASSERT_UNUSED(isSent, isSent);
 }
 

Source/WebKit/NetworkProcess/ServiceWorker/WebSWServerConnection.cpp

@@ -217,7 +217,6 @@ std::unique_ptr<ServiceWorkerFetchTask> WebSWServerConnection::createFetchTask(N
 
         serviceWorkerRegistrationIdentifier = registration->identifier();
         controlClient(loader.parameters(), *registration, request, loader.connectionToWebProcess().webProcessIdentifier());
-        loader.setResultingClientIdentifier(resultingClientIdentifier->toString());
         loader.setServiceWorkerRegistration(*registration);
     } else {
         if (!loader.parameters().serviceWorkerRegistrationIdentifier)