Handle rejected promises better for workers.

Source/core/workers/WorkerThread.cpp

 /*
  * Copyright (C) 2008 Apple 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
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 42 matching lines @@
 #include <utility>
 
 namespace blink {
 
 namespace {
 const int64_t kShortIdleHandlerDelayMs = 1000;
 const int64_t kLongIdleHandlerDelayMs = 10*1000;
 
 class MicrotaskRunner : public WebThread::TaskObserver {
 public:
+    explicit MicrotaskRunner(WorkerThread* workerThread)
+        : m_workerThread(workerThread)
+    {
+    }
+
     virtual void willProcessTask() override { }
     virtual void didProcessTask() override
     {
         Microtask::performCheckpoint();
-        V8Initializer::reportRejectedPromises();
+        if (WorkerGlobalScope* globalScope = m_workerThread->workerGlobalScope()) {
+            if (WorkerScriptController* scriptController = globalScope->script())
+                scriptController->rejectedPromises()->processQueue();
+        }
     }
+
+private:
+    // Thread owns the microtask runner; reference remains
+    // valid for the lifetime of this object.
+    WorkerThread* m_workerThread;
 };
 
 } // namespace
 
 static Mutex& threadSetMutex()
 {
     AtomicallyInitializedStaticReference(Mutex, mutex, new Mutex);
     return mutex;
 }
 
@@ skipping 224 matching lines @@
         MutexLocker lock(m_threadCreationMutex);
 
         // The worker was terminated before the thread had a chance to run.
         if (m_terminated) {
             // Notify the proxy that the WorkerGlobalScope has been disposed of.
             // This can free this thread object, hence it must not be touched afterwards.
             m_workerReportingProxy.workerThreadTerminated();
             return;
         }
 
-        m_microtaskRunner = adoptPtr(new MicrotaskRunner);
+        m_microtaskRunner = adoptPtr(new MicrotaskRunner(this));
         m_thread->addTaskObserver(m_microtaskRunner.get());
         m_thread->attachGC();
         m_workerGlobalScope = createWorkerGlobalScope(m_startupData.release());
 
         m_sharedTimer = adoptPtr(new WorkerSharedTimer(this));
         PlatformThreadData::current().threadTimers().setSharedTimer(m_sharedTimer.get());
     }
 
     // The corresponding call to stopRunLoop() is in ~WorkerScriptController().
     didStartRunLoop();
@@ skipping 229 matching lines @@
     InspectorInstrumentation::didLeaveNestedRunLoop(m_workerGlobalScope.get());
 }
 
 void WorkerThread::setWorkerInspectorController(WorkerInspectorController* workerInspectorController)
 {
     MutexLocker locker(m_workerInspectorControllerMutex);
     m_workerInspectorController = workerInspectorController;
 }
 
 } // namespace blink