Oilpan: dispose ServiceWorker (and registration) objects earlier.

Source/modules/serviceworkers/ServiceWorkerRegistration.cpp

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "config.h"
 #include "ServiceWorkerRegistration.h"
 
 #include "bindings/core/v8/CallbackPromiseAdapter.h"
 #include "bindings/core/v8/ScriptPromise.h"
 #include "bindings/core/v8/ScriptPromiseResolver.h"
@@ skipping 127 matching lines @@
     return registration;
 }
 
 ServiceWorkerRegistration::ServiceWorkerRegistration(ExecutionContext* executionContext, PassOwnPtr<WebServiceWorkerRegistration> outerRegistration)
     : ActiveDOMObject(executionContext)
     , m_outerRegistration(outerRegistration)
     , m_provider(0)
     , m_stopped(false)
 {
     ASSERT(m_outerRegistration);
+    ThreadState::current()->registerPreFinalizer(*this);
 
     if (!executionContext)
         return;
     if (ServiceWorkerContainerClient* client = ServiceWorkerContainerClient::from(executionContext))
         m_provider = client->provider();
     m_outerRegistration->setProxy(this);
 }
 
+ServiceWorkerRegistration::~ServiceWorkerRegistration()
+{
+    ASSERT(!m_outerRegistration);
+}
+
+void ServiceWorkerRegistration::dispose()
+{
+    // See ServiceWorker::dispose() comment why this explicit dispose() action is needed.
+    m_outerRegistration.clear();
+}
+
 void ServiceWorkerRegistration::trace(Visitor* visitor)
 {
     visitor->trace(m_installing);
     visitor->trace(m_waiting);
     visitor->trace(m_active);
     RefCountedGarbageCollectedEventTargetWithInlineData<ServiceWorkerRegistration>::trace(visitor);
     HeapSupplementable<ServiceWorkerRegistration>::trace(visitor);
     ActiveDOMObject::trace(visitor);
 }
 
 bool ServiceWorkerRegistration::hasPendingActivity() const
 {
     return !m_stopped;
 }
 
 void ServiceWorkerRegistration::stop()
 {
     if (m_stopped)
         return;
     m_stopped = true;
     m_outerRegistration->proxyStopped();
 }
 
 } // namespace blink