Worker: Introduce per-global-scope task scheduler

third_party/WebKit/Source/platform/scheduler/child/webthread_impl_for_worker_scheduler.cc

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "platform/scheduler/child/webthread_impl_for_worker_scheduler.h"
 
 #include "base/bind.h"
 #include "base/location.h"
 #include "base/memory/ptr_util.h"
 #include "base/single_thread_task_runner.h"
@@ skipping 44 matching lines @@
                    base::Unretained(this), &completion));
     completion.Wait();
   }
   thread_->Stop();
 }
 
 void WebThreadImplForWorkerScheduler::InitOnThread(
     base::WaitableEvent* completion) {
   // TODO(alexclarke): Do we need to unify virtual time for workers and the
   // main thread?
+  task_runner_delegate_ = SchedulerTqmDelegateImpl::Create(
+      thread_->message_loop(), base::MakeUnique<base::DefaultTickClock>());
   worker_scheduler_ = CreateWorkerScheduler();
   worker_scheduler_->Init();
   task_runner_ = worker_scheduler_->DefaultTaskRunner();
   idle_task_runner_ = worker_scheduler_->IdleTaskRunner();
   web_scheduler_.reset(new WebSchedulerImpl(
       worker_scheduler_.get(), worker_scheduler_->IdleTaskRunner(),
       worker_scheduler_->DefaultTaskRunner(),
       worker_scheduler_->DefaultTaskRunner()));
   base::MessageLoop::current()->AddDestructionObserver(this);
   web_task_runner_ = WebTaskRunnerImpl::Create(task_runner_);
   completion->Signal();
 }
 
 void WebThreadImplForWorkerScheduler::RestoreTaskRunnerOnThread(
     base::WaitableEvent* completion) {
   task_runner_delegate_->RestoreDefaultTaskRunner();
   completion->Signal();
 }
 
 void WebThreadImplForWorkerScheduler::WillDestroyCurrentMessageLoop() {
   task_runner_ = nullptr;
   idle_task_runner_ = nullptr;
   web_scheduler_.reset();
   worker_scheduler_.reset();
   web_task_runner_.Reset();
 }
 
 std::unique_ptr<scheduler::WorkerScheduler>
 WebThreadImplForWorkerScheduler::CreateWorkerScheduler() {
-  task_runner_delegate_ = SchedulerTqmDelegateImpl::Create(
-      thread_->message_loop(), base::MakeUnique<base::DefaultTickClock>());
   return WorkerScheduler::Create(task_runner_delegate_);
 }
 
 blink::PlatformThreadId WebThreadImplForWorkerScheduler::ThreadId() const {
   return thread_->GetThreadId();
 }
 
 blink::WebScheduler* WebThreadImplForWorkerScheduler::Scheduler() const {
   return web_scheduler_.get();
 }
@@ skipping 17 matching lines @@
   worker_scheduler_->AddTaskObserver(observer);
 }
 
 void WebThreadImplForWorkerScheduler::RemoveTaskObserverInternal(
     base::MessageLoop::TaskObserver* observer) {
   worker_scheduler_->RemoveTaskObserver(observer);
 }
 
 }  // namespace scheduler
 }  // namespace blink