Oilpan: dispose ServiceWorker (and registration) objects earlier.

Source/modules/serviceworkers/ServiceWorker.h

Index: Source/modules/serviceworkers/ServiceWorker.h
diff --git a/Source/modules/serviceworkers/ServiceWorker.h b/Source/modules/serviceworkers/ServiceWorker.h
index b236482cbafe8beb81e43ad9f11ffe157f3004c1..261880e6d1ea4ddc16e1316df6cf7b39d26be652 100644
--- a/Source/modules/serviceworkers/ServiceWorker.h
+++ b/Source/modules/serviceworkers/ServiceWorker.h
@@ -46,6 +46,7 @@ namespace blink {
 class ScriptPromiseResolver;
 
 class ServiceWorker final : public AbstractWorker, public WebServiceWorkerProxy {
+    WILL_BE_USING_PRE_FINALIZER(ServiceWorker, dispose);
     DEFINE_WRAPPERTYPEINFO();
 public:
     // For CallbackPromiseAdapter
@@ -53,6 +54,8 @@ public:
     static PassRefPtrWillBeRawPtr<ServiceWorker> take(ScriptPromiseResolver*, WebType* worker);
 
     static PassRefPtrWillBeRawPtr<ServiceWorker> from(ExecutionContext*, WebType*);
+
+    ~ServiceWorker() override;
     static void dispose(WebType*);
 
     void postMessage(ExecutionContext*, PassRefPtr<SerializedScriptValue> message, const MessagePortArray*, ExceptionState&);
@@ -90,6 +93,8 @@ private:
     virtual bool hasPendingActivity() const override;
     virtual void stop() override;
 
+    void dispose();
+
     OwnPtr<WebServiceWorker> m_outerWorker;
     ProxyState m_proxyState;
 };