Worker: Introduce per-global-scope task scheduler

third_party/WebKit/Source/core/workers/WorkerGlobalScope.cpp

 /*
  * Copyright (C) 2008 Apple Inc. All Rights Reserved.
  * Copyright (C) 2009, 2011 Google Inc. All Rights Reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
@@ skipping 299 matching lines @@
     WorkerClients* worker_clients)
     : url_(url),
       user_agent_(user_agent),
       v8_cache_options_(kV8CacheOptionsDefault),
       script_controller_(
           WorkerOrWorkletScriptController::Create(this, thread->GetIsolate())),
       thread_(thread),
       closing_(false),
       event_queue_(WorkerEventQueue::Create(this)),
       worker_clients_(worker_clients),
-      timers_(
-          Platform::Current()->CurrentThread()->Scheduler()->TimerTaskRunner()),
+      timers_(TaskRunnerHelper::Get(TaskType::kTimer, this)),
       time_origin_(time_origin),
       last_pending_error_event_id_(0) {
   InstanceCounters::IncrementCounter(
       InstanceCounters::kWorkerGlobalScopeCounter);
   SetSecurityOrigin(SecurityOrigin::Create(url));
   if (starter_origin_privilage_data)
     GetSecurityOrigin()->TransferPrivilegesFrom(
         std::move(starter_origin_privilage_data));
 
   if (worker_clients_)
@@ skipping 44 matching lines @@
   visitor->Trace(timers_);
   visitor->Trace(event_listeners_);
   visitor->Trace(pending_error_events_);
   ExecutionContext::Trace(visitor);
   EventTargetWithInlineData::Trace(visitor);
   SecurityContext::Trace(visitor);
   Supplementable<WorkerGlobalScope>::Trace(visitor);
 }
 
 }  // namespace blink