Worker: Remove legacy on-the-main-thread shared worker script loading

Off-the-main-thread shared worker script loading was enabled by default in M76.
The legacy on-the-main-thread shared worker script loading is no longer
necessary. This CL removes it.

This CL removes code wrapped with the runtime flag in a mechanical way. After
this CL, I'll do more structural changes, for example, remove
ServiceWorkerNetworkProviderForSharedWorker.

Bug: 987850
Change-Id: I388a22fdd3a7b14f6d3f70c8e74108920025676c
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1718471
Commit-Queue: Hiroki Nakagawa <nhiroki@chromium.org>
Reviewed-by: Kenichi Ishibashi <bashi@chromium.org>
Reviewed-by: Kinuko Yasuda <kinuko@chromium.org>
Cr-Commit-Position: refs/heads/master@{#681476}

content/renderer/loader/web_worker_fetch_context_impl.cc

@@ -401,10 +401,9 @@ void WebWorkerFetchContextImpl::WillSendRequest(blink::WebURLRequest& request) {
         ancestor_frame_id_, request, WebURLRequestToResourceType(request)));
   }
   if (response_override_) {
-    DCHECK(blink::features::IsPlzDedicatedWorkerEnabled() ||
-           blink::features::IsOffMainThreadSharedWorkerScriptFetchEnabled());
     using RequestContextType = blink::mojom::RequestContextType;
-    DCHECK(request.GetRequestContext() == RequestContextType::WORKER ||
+    DCHECK((blink::features::IsPlzDedicatedWorkerEnabled() &&
+            request.GetRequestContext() == RequestContextType::WORKER) ||
            request.GetRequestContext() == RequestContextType::SHARED_WORKER)
         << request.GetRequestContext();
     extra_data->set_navigation_response_override(std::move(response_override_));
@@ -522,7 +521,6 @@ void WebWorkerFetchContextImpl::set_client_id(const std::string& client_id) {
 
 void WebWorkerFetchContextImpl::SetResponseOverrideForMainScript(
     std::unique_ptr<NavigationResponseOverrideParameters> response_override) {
-  DCHECK(blink::features::IsOffMainThreadSharedWorkerScriptFetchEnabled());
   DCHECK(!response_override_);
   response_override_ = std::move(response_override);
 }

content/renderer/worker/embedded_shared_worker_stub.cc

@@ -167,23 +167,13 @@ void EmbeddedSharedWorkerStub::WorkerContextDestroyed() {
 
 std::unique_ptr<blink::WebServiceWorkerNetworkProvider>
 EmbeddedSharedWorkerStub::CreateServiceWorkerNetworkProvider() {
-  if (blink::features::IsOffMainThreadSharedWorkerScriptFetchEnabled()) {
-    // Off-the-main-thread shared worker script fetch:
-    // |response_override_| will be passed to WebWorkerFetchContextImpl in
-    // CreateWorkerFetchContext() and consumed during off-the-main-thread
-    // shared worker script fetch.
-    return ServiceWorkerNetworkProviderForSharedWorker::Create(
-        std::move(service_worker_provider_info_), std::move(controller_info_),
-        subresource_loader_factory_bundle_, IsOriginSecure(url_),
-        nullptr /* response_override */);
-  }
-
-  // |response_override_| is passed to DocumentLoader and consumed during
-  // on-the-main-thread shared worker script fetch.
+  // |response_override_| will be passed to WebWorkerFetchContextImpl in
+  // CreateWorkerFetchContext() and consumed during shared worker script fetch
+  // on the worker thread.
   return ServiceWorkerNetworkProviderForSharedWorker::Create(
       std::move(service_worker_provider_info_), std::move(controller_info_),
       subresource_loader_factory_bundle_, IsOriginSecure(url_),
-      std::move(response_override_));
+      nullptr /* response_override */);
 }
 
 scoped_refptr<blink::WebWorkerFetchContext>
@@ -219,11 +209,9 @@ EmbeddedSharedWorkerStub::CreateWorkerFetchContext(
   worker_fetch_context->set_is_secure_context(IsOriginSecure(url_));
   worker_fetch_context->set_origin_url(url_.GetOrigin());
 
-  if (response_override_) {
-    DCHECK(blink::features::IsOffMainThreadSharedWorkerScriptFetchEnabled());
-    worker_fetch_context->SetResponseOverrideForMainScript(
-        std::move(response_override_));
-  }
+  DCHECK(response_override_);
+  worker_fetch_context->SetResponseOverrideForMainScript(
+      std::move(response_override_));
 
   return worker_fetch_context;
 }

third_party/blink/common/features.cc

@@ -110,11 +110,6 @@ const base::Feature kOffMainThreadDedicatedWorkerScriptFetch{
 const base::Feature kOffMainThreadServiceWorkerScriptFetch{
     "OffMainThreadServiceWorkerScriptFetch", base::FEATURE_ENABLED_BY_DEFAULT};
 
-// Enable off-the-main-thread shared worker script fetch.
-// (https://crbug.com/924041)
-const base::Feature kOffMainThreadSharedWorkerScriptFetch{
-    "OffMainThreadSharedWorkerScriptFetch", base::FEATURE_ENABLED_BY_DEFAULT};
-
 // Enable browser-initiated dedicated worker script loading
 // (PlzDedicatedWorker). https://crbug.com/906991
 const base::Feature kPlzDedicatedWorker{"PlzDedicatedWorker",
@@ -280,14 +275,6 @@ const base::Feature kLightweightNoStatePrefetch{
 const base::Feature kScrollbarInjectScrollGestures{
     "ScrollbarInjectScrollGestures", base::FEATURE_ENABLED_BY_DEFAULT};
 
-bool IsOffMainThreadSharedWorkerScriptFetchEnabled() {
-  // Off-the-main-thread shared worker script fetch depends on PlzSharedWorker
-  // (NetworkService).
-  return base::FeatureList::IsEnabled(network::features::kNetworkService) &&
-         base::FeatureList::IsEnabled(
-             features::kOffMainThreadSharedWorkerScriptFetch);
-}
-
 bool IsPlzDedicatedWorkerEnabled() {
   // PlzDedicatedWorker depends on off-the-main-thread dedicated worker script
   // fetch and NetworkService.

third_party/blink/public/common/features.h

@@ -87,9 +87,6 @@ BLINK_COMMON_EXPORT extern const base::Feature kAudioWorkletRealtimeThread;
 
 BLINK_COMMON_EXPORT extern const base::Feature kLightweightNoStatePrefetch;
 
-// Returns true when off-the-main-thread shared worker script fetch is enabled.
-BLINK_COMMON_EXPORT bool IsOffMainThreadSharedWorkerScriptFetchEnabled();
-
 // Returns true when PlzDedicatedWorker is enabled.
 BLINK_COMMON_EXPORT bool IsPlzDedicatedWorkerEnabled();
 

third_party/blink/renderer/core/exported/web_shared_worker_impl.h

@@ -63,7 +63,6 @@ class SharedWorkerThread;
 class WebSharedWorkerClient;
 class WebString;
 class WebURL;
-class WorkerClassicScriptLoader;
 
 // This class is used by the worker process code to talk to the SharedWorker
 // implementation. This is basically accessed on the main thread, but some
@@ -122,8 +121,6 @@ class CORE_EXPORT WebSharedWorkerImpl final : public WebSharedWorker,
   // Shuts down the worker thread.
   void TerminateWorkerThread();
 
-  void DidReceiveScriptLoaderResponse();
-  void OnScriptLoaderFinished();
   void OnAppCacheSelected();
   void ContinueStartWorkerContext();
   void StartWorkerThread(
@@ -151,9 +148,6 @@ class CORE_EXPORT WebSharedWorkerImpl final : public WebSharedWorker,
   bool pause_worker_context_on_start_ = false;
   bool is_paused_on_start_ = false;
 
-  // Kept around only while main script loading is ongoing.
-  Persistent<WorkerClassicScriptLoader> main_script_loader_;
-
   WebURL script_request_url_;
   WebString name_;
   mojom::IPAddressSpace creation_address_space_;

third_party/blink/renderer/core/workers/shared_worker_global_scope.cc

@@ -54,35 +54,10 @@ SharedWorkerGlobalScope* SharedWorkerGlobalScope::Create(
     std::unique_ptr<GlobalScopeCreationParams> creation_params,
     SharedWorkerThread* thread,
     base::TimeTicks time_origin) {
-  // Off-the-main-thread worker script fetch:
-  // Initialize() is called after script fetch.
-  if (creation_params->off_main_thread_fetch_option ==
-      OffMainThreadWorkerScriptFetchOption::kEnabled) {
-    return MakeGarbageCollected<SharedWorkerGlobalScope>(
-        std::move(creation_params), thread, time_origin);
-  }
-
-  // Legacy on-the-main-thread worker script fetch (to be removed):
-  KURL response_script_url = creation_params->script_url;
-  network::mojom::ReferrerPolicy response_referrer_policy =
-      creation_params->referrer_policy;
-  mojom::IPAddressSpace response_address_space =
-      *creation_params->response_address_space;
-  // Contrary to the name, |outside_content_security_policy_headers| contains
-  // worker script's response CSP headers in this case.
-  // TODO(nhiroki): Introduce inside's csp headers field in
-  // GlobalScopeCreationParams or deprecate this code path by enabling
-  // off-the-main-thread worker script fetch by default.
-  Vector<CSPHeaderAndType> response_csp_headers =
-      creation_params->outside_content_security_policy_headers;
-  std::unique_ptr<Vector<String>> response_origin_trial_tokens =
-      std::move(creation_params->origin_trial_tokens);
-  auto* global_scope = MakeGarbageCollected<SharedWorkerGlobalScope>(
+  DCHECK_EQ(creation_params->off_main_thread_fetch_option,
+            OffMainThreadWorkerScriptFetchOption::kEnabled);
+  return MakeGarbageCollected<SharedWorkerGlobalScope>(
       std::move(creation_params), thread, time_origin);
-  global_scope->Initialize(response_script_url, response_referrer_policy,
-                           response_address_space, response_csp_headers,
-                           response_origin_trial_tokens.get());
-  return global_scope;
 }
 
 SharedWorkerGlobalScope::SharedWorkerGlobalScope(
@@ -90,10 +65,6 @@ SharedWorkerGlobalScope::SharedWorkerGlobalScope(
     SharedWorkerThread* thread,
     base::TimeTicks time_origin)
     : WorkerGlobalScope(std::move(creation_params), thread, time_origin) {
-  // When off-the-main-thread script fetch is enabled, ReadyToRunWorkerScript()
-  // will be called after an app cache is selected.
-  if (!features::IsOffMainThreadSharedWorkerScriptFetchEnabled())
-    ReadyToRunWorkerScript();
 }
 
 SharedWorkerGlobalScope::~SharedWorkerGlobalScope() = default;
@@ -143,7 +114,6 @@ void SharedWorkerGlobalScope::FetchAndRunClassicScript(
     const FetchClientSettingsObjectSnapshot& outside_settings_object,
     WorkerResourceTimingNotifier& outside_resource_timing_notifier,
     const v8_inspector::V8StackTraceId& stack_id) {
-  DCHECK(features::IsOffMainThreadSharedWorkerScriptFetchEnabled());
   DCHECK(!IsContextPaused());
 
   // Step 12. "Fetch a classic worker script given url, outside settings,
@@ -206,14 +176,12 @@ void SharedWorkerGlobalScope::Connect(MessagePortChannel channel) {
 
 void SharedWorkerGlobalScope::OnAppCacheSelected() {
   DCHECK(IsContextThread());
-  DCHECK(features::IsOffMainThreadSharedWorkerScriptFetchEnabled());
   ReadyToRunWorkerScript();
 }
 
 void SharedWorkerGlobalScope::DidReceiveResponseForClassicScript(
     WorkerClassicScriptLoader* classic_script_loader) {
   DCHECK(IsContextThread());
-  DCHECK(features::IsOffMainThreadSharedWorkerScriptFetchEnabled());
   probe::DidReceiveScriptResponse(this, classic_script_loader->Identifier());
 }
 
@@ -222,7 +190,6 @@ void SharedWorkerGlobalScope::DidFetchClassicScript(
     WorkerClassicScriptLoader* classic_script_loader,
     const v8_inspector::V8StackTraceId& stack_id) {
   DCHECK(IsContextThread());
-  DCHECK(features::IsOffMainThreadSharedWorkerScriptFetchEnabled());
 
   // Step 12. "If the algorithm asynchronously completes with null, then:"
   if (classic_script_loader->Failed()) {

third_party/blink/web_tests/VirtualTestSuites

@@ -574,93 +574,93 @@
   {
     "prefix": "omt-worker-fetch",
     "base": "external/wpt/content-security-policy/inside-worker",
-    "args": ["--enable-features=OffMainThreadDedicatedWorkerScriptFetch,PlzDedicatedWorker,OffMainThreadServiceWorkerScriptFetch,OffMainThreadSharedWorkerScriptFetch"]
+    "args": ["--enable-features=OffMainThreadDedicatedWorkerScriptFetch,PlzDedicatedWorker,OffMainThreadServiceWorkerScriptFetch"]
   },
   {
     "prefix": "omt-worker-fetch",
     "base": "external/wpt/content-security-policy/worker-src",
-    "args": ["--enable-features=OffMainThreadDedicatedWorkerScriptFetch,PlzDedicatedWorker,OffMainThreadServiceWorkerScriptFetch,OffMainThreadSharedWorkerScriptFetch"]
+    "args": ["--enable-features=OffMainThreadDedicatedWorkerScriptFetch,PlzDedicatedWorker,OffMainThreadServiceWorkerScriptFetch"]
   },
   {
     "prefix": "omt-worker-fetch",
     "base": "external/wpt/fetch/",
-    "args": ["--enable-features=OffMainThreadDedicatedWorkerScriptFetch,PlzDedicatedWorker,OffMainThreadServiceWorkerScriptFetch,OffMainThreadSharedWorkerScriptFetch"]
+    "args": ["--enable-features=OffMainThreadDedicatedWorkerScriptFetch,PlzDedicatedWorker,OffMainThreadServiceWorkerScriptFetch"]
   },
   {
     "prefix": "omt-worker-fetch",
     "base": "external/wpt/html/browsers/offline/appcache/workers/",
-    "args": ["--enable-features=OffMainThreadDedicatedWorkerScriptFetch,PlzDedicatedWorker,OffMainThreadServiceWorkerScriptFetch,OffMainThreadSharedWorkerScriptFetch"]
+    "args": ["--enable-features=OffMainThreadDedicatedWorkerScriptFetch,PlzDedicatedWorker,OffMainThreadServiceWorkerScriptFetch"]
   },
   {
     "prefix": "omt-worker-fetch",
     "base": "external/wpt/mixed-content/classic-data-worker-fetch",
-    "args": ["--enable-features=OffMainThreadDedicatedWorkerScriptFetch,PlzDedicatedWorker,OffMainThreadServiceWorkerScriptFetch,OffMainThreadSharedWorkerScriptFetch"]
+    "args": ["--enable-features=OffMainThreadDedicatedWorkerScriptFetch,PlzDedicatedWorker,OffMainThreadServiceWorkerScriptFetch"]
   },
   {
     "prefix": "omt-worker-fetch",
     "base": "external/wpt/mixed-content/module-data-worker-import",
-    "args": ["--enable-features=OffMainThreadDedicatedWorkerScriptFetch,PlzDedicatedWorker,OffMainThreadServiceWorkerScriptFetch,OffMainThreadSharedWorkerScriptFetch"]
+    "args": ["--enable-features=OffMainThreadDedicatedWorkerScriptFetch,PlzDedicatedWorker,OffMainThreadServiceWorkerScriptFetch"]
   },
   {
     "prefix": "omt-worker-fetch",
     "base": "external/wpt/mixed-content/module-worker-top-level",
-    "args": ["--enable-features=OffMainThreadDedicatedWorkerScriptFetch,PlzDedicatedWorker,OffMainThreadServiceWorkerScriptFetch,OffMainThreadSharedWorkerScriptFetch"]
+    "args": ["--enable-features=OffMainThreadDedicatedWorkerScriptFetch,PlzDedicatedWorker,OffMainThreadServiceWorkerScriptFetch"]
   },
   {
     "prefix": "omt-worker-fetch",
     "base": "external/wpt/mixed-content/worker-request",
-    "args": ["--enable-features=OffMainThreadDedicatedWorkerScriptFetch,PlzDedicatedWorker,OffMainThreadServiceWorkerScriptFetch,OffMainThreadSharedWorkerScriptFetch"]
+    "args": ["--enable-features=OffMainThreadDedicatedWorkerScriptFetch,PlzDedicatedWorker,OffMainThreadServiceWorkerScriptFetch"]
   },
   {
     "prefix": "omt-worker-fetch",
     "base": "external/wpt/referrer-policy",
-    "args": ["--enable-features=OffMainThreadDedicatedWorkerScriptFetch,PlzDedicatedWorker,OffMainThreadServiceWorkerScriptFetch,OffMainThreadSharedWorkerScriptFetch"]
+    "args": ["--enable-features=OffMainThreadDedicatedWorkerScriptFetch,PlzDedicatedWorker,OffMainThreadServiceWorkerScriptFetch"]
   },
   {
     "prefix": "omt-worker-fetch",
     "base": "external/wpt/resource-timing",
-    "args": ["--enable-features=OffMainThreadDedicatedWorkerScriptFetch,PlzDedicatedWorker,OffMainThreadServiceWorkerScriptFetch,OffMainThreadSharedWorkerScriptFetch"]
+    "args": ["--enable-features=OffMainThreadDedicatedWorkerScriptFetch,PlzDedicatedWorker,OffMainThreadServiceWorkerScriptFetch"]
   },
   {
     "prefix": "omt-worker-fetch",
     "base": "external/wpt/service-workers",
-    "args": ["--enable-features=OffMainThreadDedicatedWorkerScriptFetch,PlzDedicatedWorker,OffMainThreadServiceWorkerScriptFetch,OffMainThreadSharedWorkerScriptFetch"]
+    "args": ["--enable-features=OffMainThreadDedicatedWorkerScriptFetch,PlzDedicatedWorker,OffMainThreadServiceWorkerScriptFetch"]
   },
   {
     "prefix": "omt-worker-fetch",
     "base": "external/wpt/upgrade-insecure-requests",
-    "args": ["--enable-features=OffMainThreadDedicatedWorkerScriptFetch,PlzDedicatedWorker,OffMainThreadServiceWorkerScriptFetch,OffMainThreadSharedWorkerScriptFetch"]
+    "args": ["--enable-features=OffMainThreadDedicatedWorkerScriptFetch,PlzDedicatedWorker,OffMainThreadServiceWorkerScriptFetch"]
   },
   {
     "prefix": "omt-worker-fetch",
     "base": "external/wpt/workers",
-    "args": ["--enable-features=OffMainThreadDedicatedWorkerScriptFetch,PlzDedicatedWorker,OffMainThreadServiceWorkerScriptFetch,OffMainThreadSharedWorkerScriptFetch"]
+    "args": ["--enable-features=OffMainThreadDedicatedWorkerScriptFetch,PlzDedicatedWorker,OffMainThreadServiceWorkerScriptFetch"]
   },
   {
     "prefix": "omt-worker-fetch",
     "base": "external/wpt/xhr",
-    "args": ["--enable-features=OffMainThreadDedicatedWorkerScriptFetch,PlzDedicatedWorker,OffMainThreadServiceWorkerScriptFetch,OffMainThreadSharedWorkerScriptFetch"]
+    "args": ["--enable-features=OffMainThreadDedicatedWorkerScriptFetch,PlzDedicatedWorker,OffMainThreadServiceWorkerScriptFetch"]
   },
   {
     "prefix": "omt-worker-fetch",
     "base": "fast/workers",
-    "args": ["--enable-features=OffMainThreadDedicatedWorkerScriptFetch,PlzDedicatedWorker,OffMainThreadServiceWorkerScriptFetch,OffMainThreadSharedWorkerScriptFetch"]
+    "args": ["--enable-features=OffMainThreadDedicatedWorkerScriptFetch,PlzDedicatedWorker,OffMainThreadServiceWorkerScriptFetch"]
   },
   {
     "prefix": "omt-worker-fetch",
     "base": "http/tests/origin_trials",
-    "args": ["--enable-features=OffMainThreadDedicatedWorkerScriptFetch,PlzDedicatedWorker,OffMainThreadServiceWorkerScriptFetch,OffMainThreadSharedWorkerScriptFetch"]
+    "args": ["--enable-features=OffMainThreadDedicatedWorkerScriptFetch,PlzDedicatedWorker,OffMainThreadServiceWorkerScriptFetch"]
   },
   {
     "prefix": "omt-worker-fetch",
     "base": "http/tests/security/cors-rfc1918",
-    "args": ["--enable-features=OffMainThreadDedicatedWorkerScriptFetch,PlzDedicatedWorker,OffMainThreadServiceWorkerScriptFetch,OffMainThreadSharedWorkerScriptFetch",
+    "args": ["--enable-features=OffMainThreadDedicatedWorkerScriptFetch,PlzDedicatedWorker,OffMainThreadServiceWorkerScriptFetch",
              "--enable-blink-features=CorsRFC1918"]
   },
   {
     "prefix": "omt-worker-fetch",
     "base": "http/tests/workers",
-    "args": ["--enable-features=OffMainThreadDedicatedWorkerScriptFetch,PlzDedicatedWorker,OffMainThreadServiceWorkerScriptFetch,OffMainThreadSharedWorkerScriptFetch"]
+    "args": ["--enable-features=OffMainThreadDedicatedWorkerScriptFetch,PlzDedicatedWorker,OffMainThreadServiceWorkerScriptFetch"]
   },
   {
     "prefix": "not-omt-sw-fetch",