Worker: Introduce per-global-scope task scheduler

third_party/WebKit/Source/core/workers/WorkerThread.h

Index: third_party/WebKit/Source/core/workers/WorkerThread.h
diff --git a/third_party/WebKit/Source/core/workers/WorkerThread.h b/third_party/WebKit/Source/core/workers/WorkerThread.h
index eba1dc13bc5ce66fc4567d55980072b57275afa6..e8c089f66482197f522ceb1764b142a2cdd12c0c 100644
--- a/third_party/WebKit/Source/core/workers/WorkerThread.h
+++ b/third_party/WebKit/Source/core/workers/WorkerThread.h
@@ -33,10 +33,12 @@
 #include "core/frame/csp/ContentSecurityPolicy.h"
 #include "core/workers/ParentFrameTaskRunners.h"
 #include "core/workers/WorkerLoaderProxy.h"
+#include "core/workers/WorkerTaskRunners.h"
 #include "core/workers/WorkerThreadLifecycleObserver.h"
 #include "platform/LifecycleNotifier.h"
 #include "platform/WaitableEvent.h"
 #include "platform/WebTaskRunner.h"
+#include "platform/scheduler/child/worker_global_scope_scheduler.h"
 #include "platform/wtf/Forward.h"
 #include "platform/wtf/Functional.h"
 #include "platform/wtf/PassRefPtr.h"
@@ -92,7 +94,6 @@ class CORE_EXPORT WorkerThreadLifecycleContext final
 //    If the running task is for debugger, it's guaranteed to finish without
 //    any interruptions.
 //  - Queued tasks never run.
-//  - postTask() and appendDebuggerTask() reject posting new tasks.
 class CORE_EXPORT WorkerThread : public WebThread::TaskObserver {
  public:
   // Represents how this thread is terminated. Used for UMA. Append only.
@@ -137,9 +138,6 @@ class CORE_EXPORT WorkerThread : public WebThread::TaskObserver {
     return worker_reporting_proxy_;
   }
 
-  void PostTask(const WebTraceLocation&, std::unique_ptr<WTF::Closure>);
-  void PostTask(const WebTraceLocation&,
-                std::unique_ptr<WTF::CrossThreadClosure>);
   void AppendDebuggerTask(std::unique_ptr<CrossThreadClosure>);
 
   // Runs only debugger tasks while paused in debugger.
@@ -176,6 +174,14 @@ class CORE_EXPORT WorkerThread : public WebThread::TaskObserver {
     return parent_frame_task_runners_.Get();
   }
 
+  RefPtr<WorkerTaskRunners> GetWorkerTaskRunners() const {
+    return worker_task_runners_;
+  }
+
+  scheduler::WorkerGlobalScopeScheduler* GetGlobalScopeScheduler() const {
+    return global_scope_scheduler_.get();
+  }
+
  protected:
   WorkerThread(PassRefPtr<WorkerLoaderProxy>, WorkerReportingProxy&);
 
@@ -243,13 +249,11 @@ class CORE_EXPORT WorkerThread : public WebThread::TaskObserver {
   // |m_threadStateMutex| acquired.
   void ForciblyTerminateExecution(const MutexLocker&, ExitCode);
 
-  // Returns true if termination or shutdown sequence has started. This is
-  // thread safe.
-  // Note that this returns false when the sequence has already started but it
-  // hasn't been notified to the calling thread.
-  bool IsInShutdown();
+  // Initializes a global scope. |global_scope_creation| event is signaled when
+  // a global scope is created.
+  void InitializeOnWorkerThread(std::unique_ptr<WorkerThreadStartupData>,
+                                WaitableEvent* global_scope_creation);
 
-  void InitializeOnWorkerThread(std::unique_ptr<WorkerThreadStartupData>);
   void PrepareForShutdownOnWorkerThread();
   void PerformShutdownOnWorkerThread();
   template <WTF::FunctionThreadAffinity threadAffinity>
@@ -294,7 +298,14 @@ class CORE_EXPORT WorkerThread : public WebThread::TaskObserver {
 
   RefPtr<WorkerLoaderProxy> worker_loader_proxy_;
   WorkerReportingProxy& worker_reporting_proxy_;
+
   CrossThreadPersistent<ParentFrameTaskRunners> parent_frame_task_runners_;
+  RefPtr<WorkerTaskRunners> worker_task_runners_;
+
+  // Tasks managed by this scheduler are canceled when the global scope is
+  // closed.
+  std::unique_ptr<scheduler::WorkerGlobalScopeScheduler>
+      global_scope_scheduler_;
 
   // This lock protects |m_globalScope|, |m_requestedToTerminate|,
   // |m_threadState|, |m_runningDebuggerTask| and |m_exitCode|.