Worker: Introduce per-global-scope task scheduler

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

Index: third_party/WebKit/Source/core/workers/WorkerOrWorkletGlobalScope.cpp
diff --git a/third_party/WebKit/Source/core/workers/WorkerOrWorkletGlobalScope.cpp b/third_party/WebKit/Source/core/workers/WorkerOrWorkletGlobalScope.cpp
index 5ae838b150bbfba3784b01c9b5f45b530a90a50f..30c0598c0c19fc9730cddda8645d3b77de074663 100644
--- a/third_party/WebKit/Source/core/workers/WorkerOrWorkletGlobalScope.cpp
+++ b/third_party/WebKit/Source/core/workers/WorkerOrWorkletGlobalScope.cpp
@@ -5,6 +5,7 @@
 #include "core/workers/WorkerOrWorkletGlobalScope.h"
 
 #include "core/dom/ExecutionContextTask.h"
+#include "core/dom/TaskRunnerHelper.h"
 #include "core/frame/Deprecation.h"
 #include "core/inspector/ConsoleMessage.h"
 #include "core/probe/CoreProbes.h"
@@ -37,7 +38,7 @@ void WorkerOrWorkletGlobalScope::addDeprecationMessage(
 }
 
 void WorkerOrWorkletGlobalScope::postTask(
-    TaskType,
+    TaskType type,
     const WebTraceLocation& location,
     std::unique_ptr<ExecutionContextTask> task,
     const String& taskNameForInstrumentation) {
@@ -49,10 +50,11 @@ void WorkerOrWorkletGlobalScope::postTask(
     probe::asyncTaskScheduled(this, "Worker task", task.get());
   }
 
-  thread()->postTask(
-      location, crossThreadBind(&WorkerOrWorkletGlobalScope::runTask,
-                                wrapCrossThreadWeakPersistent(this),
-                                WTF::passed(std::move(task)), isInstrumented));
+  TaskRunnerHelper::get(type, this)
+      ->postTask(location,
+                 crossThreadBind(&WorkerOrWorkletGlobalScope::runTask,
+                                 wrapCrossThreadWeakPersistent(this),
+                                 WTF::passed(std::move(task)), isInstrumented));
 }
 
 void WorkerOrWorkletGlobalScope::runTask(