Implement dumb URLLoader{Factory} for ServiceWorker script loading (for try)

content/browser/service_worker/service_worker_version.cc

Index: content/browser/service_worker/service_worker_version.cc
diff --git a/content/browser/service_worker/service_worker_version.cc b/content/browser/service_worker/service_worker_version.cc
index 306710a8ca16c874b225c158da2ed44dc34218af..ac6eb2a42eadf248a912bf3ef461c299aff70b74 100644
--- a/content/browser/service_worker/service_worker_version.cc
+++ b/content/browser/service_worker/service_worker_version.cc
@@ -846,6 +846,9 @@ ServiceWorkerVersion::PendingRequest::~PendingRequest() {}
 
 void ServiceWorkerVersion::OnThreadStarted() {
   DCHECK_EQ(EmbeddedWorkerStatus::STARTING, running_status());
+  DCHECK(provider_host_);
+  provider_host_->SetReadyToSendMessagesToWorker(
+      embedded_worker()->thread_id());
   // Activate ping/pong now that JavaScript execution will start.
   ping_controller_->Activate();
 }
@@ -855,6 +858,11 @@ void ServiceWorkerVersion::OnStarting() {
     observer.OnRunningStateChanged(this);
 }
 
+void ServiceWorkerVersion::OnStartWorkerMessageSent() {
+  DCHECK(pending_provider_host_);
+  context()->AddProviderHost(std::move(pending_provider_host_));
+}
+
 void ServiceWorkerVersion::OnStarted() {
   DCHECK_EQ(EmbeddedWorkerStatus::RUNNING, running_status());
   RestartTick(&idle_time_);
@@ -903,14 +911,7 @@ void ServiceWorkerVersion::OnDetached(EmbeddedWorkerStatus old_status) {
 }
 
 void ServiceWorkerVersion::OnScriptLoaded() {
-  DCHECK(GetMainScriptHttpResponseInfo() ||
-         // TODO(scottmg|falken): This DCHECK is currently triggered in
-         // --network-service because ServiceWorkerReadFromCacheJob isn't being
-         // used to retrieve the service worker js. This should be removed once
-         // that's done.
-         (IsBrowserSideNavigationEnabled() &&
-          base::CommandLine::ForCurrentProcess()->HasSwitch(
-              switches::kEnableNetworkService)));
+  DCHECK(GetMainScriptHttpResponseInfo());
   if (IsInstalled(status()))
     UMA_HISTOGRAM_BOOLEAN("ServiceWorker.ScriptLoadSuccess", true);
 }
@@ -1465,6 +1466,11 @@ void ServiceWorkerVersion::StartWorkerInternal() {
 
   StartTimeoutTimer();
 
+  DCHECK(!pending_provider_host_);
+  pending_provider_host_ =
+      ServiceWorkerProviderHost::PreCreateForController(this, context());
+  provider_host_ = pending_provider_host_->AsWeakPtr();
+
   auto params = base::MakeUnique<EmbeddedWorkerStartParams>();
   params->service_worker_version_id = version_id_;
   params->scope = scope_;
@@ -1473,7 +1479,8 @@ void ServiceWorkerVersion::StartWorkerInternal() {
   params->pause_after_download = pause_after_download_;
 
   embedded_worker_->Start(
-      std::move(params), mojo::MakeRequest(&event_dispatcher_),
+      std::move(params), pending_provider_host_->AsWeakPtr(),
+      mojo::MakeRequest(&event_dispatcher_),
       base::Bind(&ServiceWorkerVersion::OnStartSentAndScriptEvaluated,
                  weak_factory_.GetWeakPtr()));
   event_dispatcher_.set_connection_error_handler(base::Bind(