service worker: Move ServiceWorkerGlobalScopeProxy off Oilpan

The motivation is to avoid creating GarbageCollected objects in
WebEmbeddedWorkerImpl so that we can start service worker on the IO thread,
not on the main thread. The IO thread runs without Oilpan and thus we can't
create GarbageCollected objects on the IO thread.

ServiceWorkerGlobalScopeProxy was a GarbageCollected object because it
contained ParentExecutionContextTaskRunners which is also a
GarbageCollected object. The only usage of the task runners was to get
the default task runner so we can replace it with
Thread::Current()->GetTaskRunner(), which returns a non GarbageCollected
task runner.

After this CL, ServiceWorkerThread owns ServiceWorkerGlobalScopeProxy as
a unique_ptr, not a Persistent. The ownership of these classes are as
follows and there seems no cycle ownership, so that's fine IIUC.

WebEmbeddedWorkerImpl --(unique_ptr)--> ServiceWorkerThread
ServiceWorkerThread --(was Persistent, now unique_ptr)--> ServiceWorkerGlobalScopeProxy
ServiceWorkerThread --(CrossThreadPersistent)--> ServiceWorkerGlobalScope
ServiceWorkerGlobalScopeProxy --(CrossThreadPersistent)--> ServiceWorkerGlobalScope
ServiceWorkerGlobalScope --(raw reference)--> ServiceWorkerGlobalScopeProxy
ServiceWorkerGlobalScope --(raw ptr)--> ServiceWorkerThread

Bug: 988335

Change-Id: I5c9104e73300ac14b56f7ad9b337d71c53321d02
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1725530Reviewed-by: Hiroki Nakagawa <nhiroki@chromium.org>
Commit-Queue: Kenichi Ishibashi <bashi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#683105}

third_party/blink/renderer/modules/service_worker/service_worker_global_scope_proxy.cc

@@ -47,7 +47,6 @@
 #include "third_party/blink/renderer/core/inspector/console_message.h"
 #include "third_party/blink/renderer/core/messaging/message_port.h"
 #include "third_party/blink/renderer/core/origin_trials/origin_trials.h"
-#include "third_party/blink/renderer/core/workers/parent_execution_context_task_runners.h"
 #include "third_party/blink/renderer/core/workers/worker_global_scope.h"
 #include "third_party/blink/renderer/core/workers/worker_thread.h"
 #include "third_party/blink/renderer/modules/exported/web_embedded_worker_impl.h"
@@ -61,11 +60,11 @@
 
 namespace blink {
 
-ServiceWorkerGlobalScopeProxy* ServiceWorkerGlobalScopeProxy::Create(
-    WebEmbeddedWorkerImpl& embedded_worker,
-    WebServiceWorkerContextClient& client) {
-  return MakeGarbageCollected<ServiceWorkerGlobalScopeProxy>(embedded_worker,
-                                                             client);
+std::unique_ptr<ServiceWorkerGlobalScopeProxy>
+ServiceWorkerGlobalScopeProxy::Create(WebEmbeddedWorkerImpl& embedded_worker,
+                                      WebServiceWorkerContextClient& client) {
+  return std::make_unique<ServiceWorkerGlobalScopeProxy>(embedded_worker,
+                                                         client);
 }
 
 ServiceWorkerGlobalScopeProxy::~ServiceWorkerGlobalScopeProxy() {
@@ -74,10 +73,6 @@ ServiceWorkerGlobalScopeProxy::~ServiceWorkerGlobalScopeProxy() {
   DCHECK(!embedded_worker_);
 }
 
-void ServiceWorkerGlobalScopeProxy::Trace(blink::Visitor* visitor) {
-  visitor->Trace(parent_execution_context_task_runners_);
-}
-
 void ServiceWorkerGlobalScopeProxy::BindServiceWorker(
     mojo::ScopedMessagePipeHandle request) {
   DCHECK_CALLED_ON_VALID_THREAD(worker_thread_checker_);
@@ -264,8 +259,7 @@ void ServiceWorkerGlobalScopeProxy::DidCloseWorkerGlobalScope() {
   // ServiceWorkerGlobalScope expects us to terminate the thread, so request
   // that here.
   PostCrossThreadTask(
-      *parent_execution_context_task_runners_->Get(TaskType::kInternalDefault),
-      FROM_HERE,
+      *parent_task_runner_, FROM_HERE,
       CrossThreadBindOnce(&WebEmbeddedWorkerImpl::TerminateWorkerContext,
                           CrossThreadUnretained(embedded_worker_)));
 
@@ -320,12 +314,7 @@ ServiceWorkerGlobalScopeProxy::ServiceWorkerGlobalScopeProxy(
       worker_global_scope_(nullptr) {
   DCHECK(IsMainThread());
   DETACH_FROM_THREAD(worker_thread_checker_);
-  // ServiceWorker can sometimes run tasks that are initiated by/associated
-  // with a document's frame but these documents can be from a different
-  // process. So we intentionally populate the task runners with default task
-  // runners of the main thread.
-  parent_execution_context_task_runners_ =
-      ParentExecutionContextTaskRunners::Create();
+  parent_task_runner_ = Thread::Current()->GetTaskRunner();
 }
 
 void ServiceWorkerGlobalScopeProxy::Detach() {

third_party/blink/renderer/modules/service_worker/service_worker_global_scope_proxy.h

@@ -39,7 +39,6 @@
 #include "third_party/blink/public/platform/web_string.h"
 #include "third_party/blink/public/web/modules/service_worker/web_service_worker_context_proxy.h"
 #include "third_party/blink/renderer/core/workers/worker_reporting_proxy.h"
-#include "third_party/blink/renderer/platform/heap/handle.h"
 #include "third_party/blink/renderer/platform/heap/persistent.h"
 #include "third_party/blink/renderer/platform/weborigin/kurl.h"
 #include "third_party/blink/renderer/platform/wtf/casting.h"
@@ -47,7 +46,6 @@
 
 namespace blink {
 
-class ParentExecutionContextTaskRunners;
 class ServiceWorkerGlobalScope;
 class WebEmbeddedWorkerImpl;
 class WebServiceWorkerContextClient;
@@ -64,13 +62,12 @@ class WebServiceWorkerContextClient;
 // An instance of this class is supposed to outlive until
 // workerThreadTerminated() is called by its corresponding
 // WorkerGlobalScope.
-class ServiceWorkerGlobalScopeProxy final
-    : public GarbageCollectedFinalized<ServiceWorkerGlobalScopeProxy>,
-      public WebServiceWorkerContextProxy,
-      public WorkerReportingProxy {
+class ServiceWorkerGlobalScopeProxy final : public WebServiceWorkerContextProxy,
+                                            public WorkerReportingProxy {
  public:
-  static ServiceWorkerGlobalScopeProxy* Create(WebEmbeddedWorkerImpl&,
-                                               WebServiceWorkerContextClient&);
+  static std::unique_ptr<ServiceWorkerGlobalScopeProxy> Create(
+      WebEmbeddedWorkerImpl&,
+      WebServiceWorkerContextClient&);
 
   ServiceWorkerGlobalScopeProxy(WebEmbeddedWorkerImpl&,
                                 WebServiceWorkerContextClient&);
@@ -131,8 +128,6 @@ class ServiceWorkerGlobalScopeProxy final
       mojom::blink::FetchEventPreloadHandlePtr preload_handle);
   void RequestTermination(base::OnceCallback<void(bool)> callback);
 
-  void Trace(blink::Visitor*);
-
   // Detaches this proxy object entirely from the outside world, clearing out
   // all references.
   //
@@ -150,8 +145,7 @@ class ServiceWorkerGlobalScopeProxy final
   // as part of its finalization.
   WebEmbeddedWorkerImpl* embedded_worker_;
 
-  Member<ParentExecutionContextTaskRunners>
-      parent_execution_context_task_runners_;
+  scoped_refptr<base::SingleThreadTaskRunner> parent_task_runner_;
 
   WebServiceWorkerContextClient* client_;
 

third_party/blink/renderer/modules/service_worker/service_worker_thread.cc

@@ -46,12 +46,12 @@
 namespace blink {
 
 ServiceWorkerThread::ServiceWorkerThread(
-    ServiceWorkerGlobalScopeProxy* global_scope_proxy,
+    std::unique_ptr<ServiceWorkerGlobalScopeProxy> global_scope_proxy,
     std::unique_ptr<ServiceWorkerInstalledScriptsManager>
         installed_scripts_manager,
     mojom::blink::CacheStoragePtrInfo cache_storage_info)
     : WorkerThread(*global_scope_proxy),
-      global_scope_proxy_(global_scope_proxy),
+      global_scope_proxy_(std::move(global_scope_proxy)),
       worker_backing_thread_(std::make_unique<WorkerBackingThread>(
           ThreadCreationParams(GetThreadType()))),
       installed_scripts_manager_(std::move(installed_scripts_manager)),

third_party/blink/renderer/modules/service_worker/service_worker_thread.h

@@ -47,7 +47,7 @@ class MODULES_EXPORT ServiceWorkerThread final : public WorkerThread {
  public:
   // ServiceWorkerThread owns a given ServiceWorkerGlobalScopeProxy via
   // Persistent.
-  ServiceWorkerThread(ServiceWorkerGlobalScopeProxy*,
+  ServiceWorkerThread(std::unique_ptr<ServiceWorkerGlobalScopeProxy>,
                       std::unique_ptr<ServiceWorkerInstalledScriptsManager>,
                       mojom::blink::CacheStoragePtrInfo cache_storage_info);
   ~ServiceWorkerThread() override;
@@ -84,7 +84,7 @@ class MODULES_EXPORT ServiceWorkerThread final : public WorkerThread {
           outside_settings_object,
       network::mojom::CredentialsMode);
 
-  Persistent<ServiceWorkerGlobalScopeProxy> global_scope_proxy_;
+  std::unique_ptr<ServiceWorkerGlobalScopeProxy> global_scope_proxy_;
   std::unique_ptr<WorkerBackingThread> worker_backing_thread_;
   std::unique_ptr<ServiceWorkerInstalledScriptsManager>
       installed_scripts_manager_;