Simplify ownership of a ThreadState's interruptors.

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 421 matching lines @@
     backingThread().shutdown();
 }
 
 v8::Isolate* WorkerThread::initializeIsolate()
 {
     ASSERT(isCurrentThread());
     ASSERT(!m_isolate);
     v8::Isolate* isolate = V8PerIsolateData::initialize();
     V8Initializer::initializeWorker(isolate);
 
-    m_interruptor = adoptPtr(new V8IsolateInterruptor(isolate));
-    ThreadState::current()->addInterruptor(m_interruptor.get());
+    OwnPtr<V8IsolateInterruptor> interruptor = adoptPtr(new V8IsolateInterruptor(isolate));
+    ThreadState::current()->addInterruptor(interruptor.release());
     ThreadState::current()->registerTraceDOMWrappers(isolate, V8GCController::traceDOMWrappers);
 
     return isolate;
 }
 
 void WorkerThread::willDestroyIsolate()
 {
     ASSERT(isCurrentThread());
     ASSERT(m_isolate);
     V8PerIsolateData::willBeDestroyed(m_isolate);
-    ThreadState::current()->removeInterruptor(m_interruptor.get());
 }
 
 void WorkerThread::destroyIsolate()
 {
     ASSERT(isCurrentThread());
     V8PerIsolateData::destroy(m_isolate);
 }
 
 void WorkerThread::terminateV8Execution()
 {
@@ skipping 43 matching lines @@
     InspectorInstrumentation::didLeaveNestedRunLoop(m_workerGlobalScope.get());
 }
 
 void WorkerThread::setWorkerInspectorController(WorkerInspectorController* workerInspectorController)
 {
     MutexLocker locker(m_workerInspectorControllerMutex);
     m_workerInspectorController = workerInspectorController;
 }
 
 } // namespace blink