[inspector] Extract IsolateData out of TaskRunner

This brings clear separation to tasks vs isolate management.

BUG=none

Review-Url: https://codereview.chromium.org/2885253002
Cr-Commit-Position: refs/heads/master@{#45355}

test/inspector/inspector-impl.cc

@@ -117,7 +117,7 @@ class ConnectTask : public TaskRunner::Task {
  private:
   void Run() override {
     v8::HandleScope handle_scope(isolate());
-    client_->connect(default_context());
+    client_->connect();
     if (ready_semaphore_) ready_semaphore_->Signal();
   }
 
@@ -150,7 +150,7 @@ class DisconnectTask : public TaskRunner::Task {
 class CreateContextGroupTask : public TaskRunner::Task {
  public:
   CreateContextGroupTask(InspectorClientImpl* client,
-                         TaskRunner::SetupGlobalTasks setup_global_tasks,
+                         IsolateData::SetupGlobalTasks setup_global_tasks,
                          v8::base::Semaphore* ready_semaphore,
                          int* context_group_id)
       : client_(client),
@@ -168,7 +168,7 @@ class CreateContextGroupTask : public TaskRunner::Task {
   }
 
   InspectorClientImpl* client_;
-  TaskRunner::SetupGlobalTasks setup_global_tasks_;
+  IsolateData::SetupGlobalTasks setup_global_tasks_;
   v8::base::Semaphore* ready_semaphore_;
   int* context_group_id_;
 };
@@ -184,40 +184,35 @@ InspectorClientImpl::InspectorClientImpl(TaskRunner* task_runner,
 
 InspectorClientImpl::~InspectorClientImpl() {}
 
-void InspectorClientImpl::connect(v8::Local<v8::Context> context) {
-  isolate_ = context->GetIsolate();
+void InspectorClientImpl::connect() {
+  isolate_ = task_runner_->data()->isolate();
   isolate_->AddMessageListener(MessageHandler);
   channel_.reset(new ChannelImpl(frontend_channel_));
   inspector_ = v8_inspector::V8Inspector::create(isolate_, this);
 
   if (states_.empty()) {
-    int context_group_id = TaskRunner::GetContextGroupId(context);
-    v8_inspector::StringView state;
-    sessions_[context_group_id] =
-        inspector_->connect(context_group_id, channel_.get(), state);
-    context->SetAlignedPointerInEmbedderData(kInspectorClientIndex, this);
-    v8_inspector::V8ContextInfo info(context, context_group_id,
-                                     v8_inspector::StringView());
-    info.hasMemoryOnConsole = true;
-    inspector_->contextCreated(info);
+    ConnectToContextGroup(task_runner_->default_context_group_id(),
+                          v8_inspector::StringView());
   } else {
-    for (const auto& it : states_) {
-      int context_group_id = it.first;
-      v8::Local<v8::Context> context =
-          task_runner_->GetContext(context_group_id);
-      v8_inspector::StringView state = it.second->string();
-      sessions_[context_group_id] =
-          inspector_->connect(context_group_id, channel_.get(), state);
-      context->SetAlignedPointerInEmbedderData(kInspectorClientIndex, this);
-      v8_inspector::V8ContextInfo info(context, context_group_id,
-                                       v8_inspector::StringView());
-      info.hasMemoryOnConsole = true;
-      inspector_->contextCreated(info);
-    }
+    for (const auto& it : states_)
+      ConnectToContextGroup(it.first, it.second->string());
   }
   states_.clear();
 }
 
+void InspectorClientImpl::ConnectToContextGroup(
+    int context_group_id, v8_inspector::StringView state) {
+  v8::Local<v8::Context> context =
+      task_runner_->data()->GetContext(context_group_id);
+  sessions_[context_group_id] =
+      inspector_->connect(context_group_id, channel_.get(), state);
+  context->SetAlignedPointerInEmbedderData(kInspectorClientIndex, this);
+  v8_inspector::V8ContextInfo info(context, context_group_id,
+                                   v8_inspector::StringView());
+  info.hasMemoryOnConsole = true;
+  inspector_->contextCreated(info);
+}
+
 void InspectorClientImpl::scheduleReconnect(
     v8::base::Semaphore* ready_semaphore) {
   task_runner_->Append(
@@ -240,19 +235,19 @@ void InspectorClientImpl::disconnect(bool reset_inspector) {
 }
 
 void InspectorClientImpl::scheduleCreateContextGroup(
-    TaskRunner::SetupGlobalTasks setup_global_tasks,
+    IsolateData::SetupGlobalTasks setup_global_tasks,
     v8::base::Semaphore* ready_semaphore, int* context_group_id) {
   task_runner_->Append(new CreateContextGroupTask(
       this, std::move(setup_global_tasks), ready_semaphore, context_group_id));
 }
 
 int InspectorClientImpl::createContextGroup(
-    const TaskRunner::SetupGlobalTasks& setup_global_tasks) {
+    const IsolateData::SetupGlobalTasks& setup_global_tasks) {
   v8::HandleScope handle_scope(isolate_);
+  int context_group_id = task_runner_->data()->CreateContextGroup();
   v8::Local<v8::Context> context =
-      task_runner_->NewContextGroup(setup_global_tasks);
+      task_runner_->data()->GetContext(context_group_id);
   context->SetAlignedPointerInEmbedderData(kInspectorClientIndex, this);
-  int context_group_id = TaskRunner::GetContextGroupId(context);
   v8_inspector::StringView state;
   sessions_[context_group_id] =
       inspector_->connect(context_group_id, channel_.get(), state);
@@ -278,7 +273,7 @@ bool InspectorClientImpl::formatAccessorsAsProperties(
 v8::Local<v8::Context> InspectorClientImpl::ensureDefaultContextInGroup(
     int context_group_id) {
   CHECK(isolate_);
-  return task_runner_->GetContext(context_group_id);
+  return task_runner_->data()->GetContext(context_group_id);
 }
 
 void InspectorClientImpl::setCurrentTimeMSForTest(double time) {
@@ -335,8 +330,12 @@ v8_inspector::V8Inspector* InspectorClientImpl::InspectorFromContext(
 
 v8_inspector::V8InspectorSession* InspectorClientImpl::SessionFromContext(
     v8::Local<v8::Context> context) {
-  int context_group_id = TaskRunner::GetContextGroupId(context);
-  return InspectorClientFromContext(context)->sessions_[context_group_id].get();
+  InspectorClientImpl* client = InspectorClientFromContext(context);
+  for (auto& it : client->sessions_) {
+    if (client->task_runner_->data()->GetContext(it.first) == context)
+      return it.second.get();
+  }
+  return nullptr;
 }
 
 v8_inspector::V8InspectorSession* InspectorClientImpl::session(

test/inspector/inspector-impl.h

@@ -28,7 +28,7 @@ class InspectorClientImpl : public v8_inspector::V8InspectorClient {
   void scheduleReconnect(v8::base::Semaphore* ready_semaphore);
   void scheduleDisconnect(v8::base::Semaphore* ready_semaphore);
   void scheduleCreateContextGroup(
-      TaskRunner::SetupGlobalTasks setup_global_tasks,
+      IsolateData::SetupGlobalTasks setup_global_tasks,
       v8::base::Semaphore* ready_semaphore, int* context_group_id);
 
   static v8_inspector::V8Inspector* InspectorFromContext(
@@ -62,12 +62,14 @@ class InspectorClientImpl : public v8_inspector::V8InspectorClient {
   friend class SendMessageToBackendTask;
 
   friend class ConnectTask;
-  void connect(v8::Local<v8::Context> context);
+  void connect();
+  void ConnectToContextGroup(int context_group_id,
+                             v8_inspector::StringView state);
   friend class DisconnectTask;
   void disconnect(bool reset_inspector);
   friend class CreateContextGroupTask;
   int createContextGroup(
-      const TaskRunner::SetupGlobalTasks& setup_global_tasks);
+      const IsolateData::SetupGlobalTasks& setup_global_tasks);
 
   std::unique_ptr<v8_inspector::V8Inspector> inspector_;
   std::unique_ptr<v8_inspector::V8Inspector::Channel> channel_;
@@ -88,7 +90,7 @@ class InspectorClientImpl : public v8_inspector::V8InspectorClient {
   DISALLOW_COPY_AND_ASSIGN(InspectorClientImpl);
 };
 
-class SendMessageToBackendExtension : public TaskRunner::SetupGlobalTask {
+class SendMessageToBackendExtension : public IsolateData::SetupGlobalTask {
  public:
   void Run(v8::Isolate* isolate, v8::Local<v8::ObjectTemplate> global) override;
 

test/inspector/inspector-test.cc

@@ -51,7 +51,7 @@ v8::Local<v8::String> ToV8String(v8::Isolate* isolate, const char* str) {
       .ToLocalChecked();
 }
 
-class UtilsExtension : public TaskRunner::SetupGlobalTask {
+class UtilsExtension : public IsolateData::SetupGlobalTask {
  public:
   ~UtilsExtension() override = default;
   void Run(v8::Isolate* isolate,
@@ -191,7 +191,8 @@ class UtilsExtension : public TaskRunner::SetupGlobalTask {
     v8::Isolate* isolate = args.GetIsolate();
     if (ReadFile(isolate, args[0], &chars)) {
       ExecuteStringTask(chars).RunOnTaskRunner(
-          TaskRunner::FromContext(isolate->GetCurrentContext()));
+          IsolateData::FromContext(isolate->GetCurrentContext())
+              ->task_runner());
     }
   }
 
@@ -317,7 +318,7 @@ class SetTimeoutTask : public AsyncTask {
   v8::Global<v8::Function> function_;
 };
 
-class SetTimeoutExtension : public TaskRunner::SetupGlobalTask {
+class SetTimeoutExtension : public IsolateData::SetupGlobalTask {
  public:
   void Run(v8::Isolate* isolate,
            v8::Local<v8::ObjectTemplate> global) override {
@@ -350,7 +351,7 @@ class SetTimeoutExtension : public TaskRunner::SetupGlobalTask {
           v8::Integer::New(isolate, 0), v8::Integer::New(isolate, 0),
           v8::Boolean::New(isolate, false), "setTimeout", inspector));
     }
-    TaskRunner::FromContext(context)->Append(task.release());
+    IsolateData::FromContext(context)->task_runner()->Append(task.release());
   }
 };
 
@@ -361,7 +362,7 @@ bool StrictAccessCheck(v8::Local<v8::Context> accessing_context,
   return accessing_context.IsEmpty();
 }
 
-class InspectorExtension : public TaskRunner::SetupGlobalTask {
+class InspectorExtension : public IsolateData::SetupGlobalTask {
  public:
   ~InspectorExtension() override = default;
   void Run(v8::Isolate* isolate,
@@ -531,7 +532,7 @@ void UtilsExtension::CreateContextGroup(
   }
   v8::base::Semaphore ready_semaphore(0);
   int context_group_id = 0;
-  TaskRunner::SetupGlobalTasks setup_global;
+  IsolateData::SetupGlobalTasks setup_global;
   setup_global.emplace_back(new SetTimeoutExtension());
   setup_global.emplace_back(new InspectorExtension());
   inspector_client_->scheduleCreateContextGroup(
@@ -609,7 +610,7 @@ int main(int argc, char* argv[]) {
     }
   }
 
-  TaskRunner::SetupGlobalTasks backend_extensions;
+  IsolateData::SetupGlobalTasks backend_extensions;
   backend_extensions.emplace_back(new SetTimeoutExtension());
   backend_extensions.emplace_back(new InspectorExtension());
   TaskRunner backend_runner(std::move(backend_extensions), false,
@@ -619,7 +620,7 @@ int main(int argc, char* argv[]) {
   SendMessageToBackendExtension::set_backend_task_runner(&backend_runner);
   UtilsExtension::set_backend_task_runner(&backend_runner);
 
-  TaskRunner::SetupGlobalTasks frontend_extensions;
+  IsolateData::SetupGlobalTasks frontend_extensions;
   frontend_extensions.emplace_back(new UtilsExtension());
   frontend_extensions.emplace_back(new SendMessageToBackendExtension());
   TaskRunner frontend_runner(std::move(frontend_extensions), true,

test/inspector/task-runner.cc

@@ -12,8 +12,7 @@
 
 namespace {
 
-const int kTaskRunnerIndex = 2;
-const int kContextGroupIdIndex = 3;
+const int kIsolateDataIndex = 2;
 
 void ReportUncaughtException(v8::Isolate* isolate,
                              const v8::TryCatch& try_catch) {
@@ -32,68 +31,90 @@ v8::internal::Vector<uint16_t> ToVector(v8::Local<v8::String> str) {
 
 }  //  namespace
 
-TaskRunner::TaskRunner(TaskRunner::SetupGlobalTasks setup_global_tasks,
-                       bool catch_exceptions,
-                       v8::base::Semaphore* ready_semaphore,
-                       v8::StartupData* startup_data)
-    : Thread(Options("Task Runner")),
-      setup_global_tasks_(std::move(setup_global_tasks)),
-      startup_data_(startup_data),
-      catch_exceptions_(catch_exceptions),
-      ready_semaphore_(ready_semaphore),
-      isolate_(nullptr),
-      process_queue_semaphore_(0),
-      nested_loop_count_(0) {
-  Start();
-}
-
-TaskRunner::~TaskRunner() { Join(); }
-
-void TaskRunner::InitializeIsolate() {
+IsolateData::IsolateData(TaskRunner* task_runner,
+                         IsolateData::SetupGlobalTasks setup_global_tasks,
+                         v8::StartupData* startup_data)
+    : task_runner_(task_runner),
+      setup_global_tasks_(std::move(setup_global_tasks)) {
   v8::Isolate::CreateParams params;
   params.array_buffer_allocator =
       v8::ArrayBuffer::Allocator::NewDefaultAllocator();
-  params.snapshot_blob = startup_data_;
+  params.snapshot_blob = startup_data;
   isolate_ = v8::Isolate::New(params);
   isolate_->SetMicrotasksPolicy(v8::MicrotasksPolicy::kScoped);
-  v8::Isolate::Scope isolate_scope(isolate_);
-  v8::HandleScope handle_scope(isolate_);
-  NewContextGroup(setup_global_tasks_);
-  if (ready_semaphore_) ready_semaphore_->Signal();
 }
 
-v8::Local<v8::Context> TaskRunner::NewContextGroup(
-    const TaskRunner::SetupGlobalTasks& setup_global_tasks) {
+IsolateData* IsolateData::FromContext(v8::Local<v8::Context> context) {
+  return static_cast<IsolateData*>(
+      context->GetAlignedPointerFromEmbedderData(kIsolateDataIndex));
+}
+
+int IsolateData::CreateContextGroup() {
   v8::Local<v8::ObjectTemplate> global_template =
       v8::ObjectTemplate::New(isolate_);
-  for (auto it = setup_global_tasks.begin(); it != setup_global_tasks.end();
+  for (auto it = setup_global_tasks_.begin(); it != setup_global_tasks_.end();
        ++it) {
     (*it)->Run(isolate_, global_template);
   }
   v8::Local<v8::Context> context =
       v8::Context::New(isolate_, nullptr, global_template);
-  context->SetAlignedPointerInEmbedderData(kTaskRunnerIndex, this);
-  intptr_t context_group_id = ++last_context_group_id_;
-  // Should be 2-byte aligned.
-  context->SetAlignedPointerInEmbedderData(
-      kContextGroupIdIndex, reinterpret_cast<void*>(context_group_id * 2));
+  context->SetAlignedPointerInEmbedderData(kIsolateDataIndex, this);
+  int context_group_id = ++last_context_group_id_;
   contexts_[context_group_id].Reset(isolate_, context);
-  return context;
+  return context_group_id;
 }
 
-v8::Local<v8::Context> TaskRunner::GetContext(int context_group_id) {
+v8::Local<v8::Context> IsolateData::GetContext(int context_group_id) {
   return contexts_[context_group_id].Get(isolate_);
 }
 
-int TaskRunner::GetContextGroupId(v8::Local<v8::Context> context) {
-  return static_cast<int>(
-      reinterpret_cast<intptr_t>(
-          context->GetAlignedPointerFromEmbedderData(kContextGroupIdIndex)) /
-      2);
+void IsolateData::RegisterModule(v8::Local<v8::Context> context,
+                                 v8::internal::Vector<uint16_t> name,
+                                 v8::ScriptCompiler::Source* source) {
+  v8::Local<v8::Module> module;
+  if (!v8::ScriptCompiler::CompileModule(isolate(), source).ToLocal(&module))
+    return;
+  if (!module->Instantiate(context, &IsolateData::ModuleResolveCallback))
+    return;
+  v8::Local<v8::Value> result;
+  if (!module->Evaluate(context).ToLocal(&result)) return;
+  modules_[name] = v8::Global<v8::Module>(isolate_, module);
+}
+
+v8::MaybeLocal<v8::Module> IsolateData::ModuleResolveCallback(
+    v8::Local<v8::Context> context, v8::Local<v8::String> specifier,
+    v8::Local<v8::Module> referrer) {
+  std::string str = *v8::String::Utf8Value(specifier);
+  IsolateData* data = IsolateData::FromContext(context);
+  return data->modules_[ToVector(specifier)].Get(data->isolate_);
+}
+
+TaskRunner::TaskRunner(IsolateData::SetupGlobalTasks setup_global_tasks,
+                       bool catch_exceptions,
+                       v8::base::Semaphore* ready_semaphore,
+                       v8::StartupData* startup_data)
+    : Thread(Options("Task Runner")),
+      setup_global_tasks_(std::move(setup_global_tasks)),
+      startup_data_(startup_data),
+      catch_exceptions_(catch_exceptions),
+      ready_semaphore_(ready_semaphore),
+      data_(nullptr),
+      process_queue_semaphore_(0),
+      nested_loop_count_(0) {
+  Start();
 }
 
+TaskRunner::~TaskRunner() { Join(); }
+
 void TaskRunner::Run() {
-  InitializeIsolate();
+  data_.reset(
+      new IsolateData(this, std::move(setup_global_tasks_), startup_data_));
+
+  v8::Isolate::Scope isolate_scope(isolate());
+  v8::HandleScope handle_scope(isolate());
+  default_context_group_id_ = data_->CreateContextGroup();
+
+  if (ready_semaphore_) ready_semaphore_->Signal();
   RunMessageLoop(false);
 }
 
@@ -102,13 +123,13 @@ void TaskRunner::RunMessageLoop(bool only_protocol) {
   while (nested_loop_count_ == loop_number && !is_terminated_.Value()) {
     TaskRunner::Task* task = GetNext(only_protocol);
     if (!task) return;
-    v8::Isolate::Scope isolate_scope(isolate_);
+    v8::Isolate::Scope isolate_scope(isolate());
     if (catch_exceptions_) {
-      v8::TryCatch try_catch(isolate_);
+      v8::TryCatch try_catch(isolate());
       task->RunOnTaskRunner(this);
       delete task;
       if (try_catch.HasCaught()) {
-        ReportUncaughtException(isolate_, try_catch);
+        ReportUncaughtException(isolate(), try_catch);
         fflush(stdout);
         fflush(stderr);
         _exit(0);
@@ -135,19 +156,6 @@ void TaskRunner::Terminate() {
   process_queue_semaphore_.Signal();
 }
 
-void TaskRunner::RegisterModule(v8::internal::Vector<uint16_t> name,
-                                v8::Local<v8::Module> module) {
-  modules_[name] = v8::Global<v8::Module>(isolate_, module);
-}
-
-v8::MaybeLocal<v8::Module> TaskRunner::ModuleResolveCallback(
-    v8::Local<v8::Context> context, v8::Local<v8::String> specifier,
-    v8::Local<v8::Module> referrer) {
-  std::string str = *v8::String::Utf8Value(specifier);
-  TaskRunner* runner = TaskRunner::FromContext(context);
-  return runner->modules_[ToVector(specifier)].Get(runner->isolate_);
-}
-
 TaskRunner::Task* TaskRunner::GetNext(bool only_protocol) {
   for (;;) {
     if (is_terminated_.Value()) return nullptr;
@@ -167,11 +175,6 @@ TaskRunner::Task* TaskRunner::GetNext(bool only_protocol) {
   return nullptr;
 }
 
-TaskRunner* TaskRunner::FromContext(v8::Local<v8::Context> context) {
-  return static_cast<TaskRunner*>(
-      context->GetAlignedPointerFromEmbedderData(kTaskRunnerIndex));
-}
-
 AsyncTask::AsyncTask(const char* task_name,
                      v8_inspector::V8Inspector* inspector)
     : inspector_(task_name ? inspector : nullptr) {
@@ -250,16 +253,7 @@ void ExecuteStringTask::AsyncRun() {
     v8::MaybeLocal<v8::Value> result;
     result = script->Run(context);
   } else {
-    v8::Local<v8::Module> module;
-    if (!v8::ScriptCompiler::CompileModule(isolate(), &scriptSource)
-             .ToLocal(&module)) {
-      return;
-    }
-    if (!module->Instantiate(context, &TaskRunner::ModuleResolveCallback))
-      return;
-    v8::Local<v8::Value> result;
-    if (!module->Evaluate(context).ToLocal(&result)) return;
-    TaskRunner* runner = TaskRunner::FromContext(context);
-    runner->RegisterModule(name_, module);
+    IsolateData::FromContext(context)->RegisterModule(context, name_,
+                                                      &scriptSource);
   }
 }

test/inspector/task-runner.h

@@ -16,14 +16,52 @@
 #include "src/locked-queue-inl.h"
 #include "src/vector.h"
 
-struct VectorCompare {
-  bool operator()(const v8::internal::Vector<uint16_t>& lhs,
-                  const v8::internal::Vector<uint16_t>& rhs) const {
-    for (int i = 0; i < lhs.length() && i < rhs.length(); ++i) {
-      if (lhs[i] != rhs[i]) return lhs[i] < rhs[i];
+class TaskRunner;
+
+class IsolateData {
+ public:
+  class SetupGlobalTask {
+   public:
+    virtual ~SetupGlobalTask() = default;
+    virtual void Run(v8::Isolate* isolate,
+                     v8::Local<v8::ObjectTemplate> global) = 0;
+  };
+  using SetupGlobalTasks = std::vector<std::unique_ptr<SetupGlobalTask>>;
+
+  IsolateData(TaskRunner* task_runner, SetupGlobalTasks setup_global_tasks,
+              v8::StartupData* startup_data);
+  static IsolateData* FromContext(v8::Local<v8::Context> context);
+
+  v8::Isolate* isolate() const { return isolate_; }
+  TaskRunner* task_runner() const { return task_runner_; }
+  int CreateContextGroup();
+  v8::Local<v8::Context> GetContext(int context_group_id);
+  void RegisterModule(v8::Local<v8::Context> context,
+                      v8::internal::Vector<uint16_t> name,
+                      v8::ScriptCompiler::Source* source);
+
+ private:
+  struct VectorCompare {
+    bool operator()(const v8::internal::Vector<uint16_t>& lhs,
+                    const v8::internal::Vector<uint16_t>& rhs) const {
+      for (int i = 0; i < lhs.length() && i < rhs.length(); ++i) {
+        if (lhs[i] != rhs[i]) return lhs[i] < rhs[i];
+      }
+      return false;
     }
-    return false;
-  }
+  };
+  static v8::MaybeLocal<v8::Module> ModuleResolveCallback(
+      v8::Local<v8::Context> context, v8::Local<v8::String> specifier,
+      v8::Local<v8::Module> referrer);
+
+  TaskRunner* task_runner_;
+  SetupGlobalTasks setup_global_tasks_;
+  v8::Isolate* isolate_;
+  int last_context_group_id_ = 0;
+  std::map<int, v8::Global<v8::Context>> contexts_;
+  std::map<v8::internal::Vector<uint16_t>, v8::Global<v8::Module>,
+           VectorCompare>
+      modules_;
 };
 
 class TaskRunner : public v8::base::Thread {
@@ -40,27 +78,22 @@ class TaskRunner : public v8::base::Thread {
 
    protected:
     virtual void Run() = 0;
-    v8::Isolate* isolate() const { return task_runner_->isolate_; }
+    v8::Isolate* isolate() const { return task_runner_->data_->isolate(); }
     v8::Local<v8::Context> default_context() const {
-      return task_runner_->contexts_.begin()->second.Get(isolate());
+      return task_runner_->data_->GetContext(
+          task_runner_->default_context_group_id_);
     }
 
    private:
     TaskRunner* task_runner_ = nullptr;
   };
 
-  class SetupGlobalTask {
-   public:
-    virtual ~SetupGlobalTask() = default;
-    virtual void Run(v8::Isolate* isolate,
-                     v8::Local<v8::ObjectTemplate> global) = 0;
-  };
-  using SetupGlobalTasks = std::vector<std::unique_ptr<SetupGlobalTask>>;
-
-  TaskRunner(SetupGlobalTasks setup_global_tasks, bool catch_exceptions,
-             v8::base::Semaphore* ready_semaphore,
+  TaskRunner(IsolateData::SetupGlobalTasks setup_global_tasks,
+             bool catch_exceptions, v8::base::Semaphore* ready_semaphore,
              v8::StartupData* startup_data);
   virtual ~TaskRunner();
+  IsolateData* data() const { return data_.get(); }
+  int default_context_group_id() const { return default_context_group_id_; }
 
   // Thread implementation.
   void Run() override;
@@ -72,33 +105,18 @@ class TaskRunner : public v8::base::Thread {
   // TaskRunner takes ownership.
   void Append(Task* task);
 
-  static TaskRunner* FromContext(v8::Local<v8::Context>);
-
-  v8::Local<v8::Context> NewContextGroup(
-      const SetupGlobalTasks& setup_global_tasks);
-  v8::Local<v8::Context> GetContext(int context_group_id);
-  static int GetContextGroupId(v8::Local<v8::Context> context);
-
   void Terminate();
 
-  void RegisterModule(v8::internal::Vector<uint16_t> name,
-                      v8::Local<v8::Module> module);
-  static v8::MaybeLocal<v8::Module> ModuleResolveCallback(
-      v8::Local<v8::Context> context, v8::Local<v8::String> specifier,
-      v8::Local<v8::Module> referrer);
-
  private:
-  void InitializeIsolate();
   Task* GetNext(bool only_protocol);
+  v8::Isolate* isolate() const { return data_->isolate(); }
 
-  SetupGlobalTasks setup_global_tasks_;
+  IsolateData::SetupGlobalTasks setup_global_tasks_;
   v8::StartupData* startup_data_;
   bool catch_exceptions_;
   v8::base::Semaphore* ready_semaphore_;
-
-  v8::Isolate* isolate_;
-  intptr_t last_context_group_id_ = 0;
-  std::map<intptr_t, v8::Global<v8::Context>> contexts_;
+  std::unique_ptr<IsolateData> data_;
+  int default_context_group_id_;
 
   // deferred_queue_ combined with queue_ (in this order) have all tasks in the
   // correct order. Sometimes we skip non-protocol tasks by moving them from
@@ -107,10 +125,6 @@ class TaskRunner : public v8::base::Thread {
   v8::internal::LockedQueue<Task*> deffered_queue_;
   v8::base::Semaphore process_queue_semaphore_;
 
-  std::map<v8::internal::Vector<uint16_t>, v8::Global<v8::Module>,
-           VectorCompare>
-      modules_;
-
   int nested_loop_count_;
 
   v8::base::AtomicNumber<int> is_terminated_;