Couple V8AbstractEventListener's lifetime to the V8 listeners lifetime

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

Index: third_party/WebKit/Source/core/workers/WorkerGlobalScope.h
diff --git a/third_party/WebKit/Source/core/workers/WorkerGlobalScope.h b/third_party/WebKit/Source/core/workers/WorkerGlobalScope.h
index 51da5e3e2bdaee531e70ec17ecdfa6c5be6f74a8..0a0c4cb4f0b8d8295f4e366fce19229b0d15b65a 100644
--- a/third_party/WebKit/Source/core/workers/WorkerGlobalScope.h
+++ b/third_party/WebKit/Source/core/workers/WorkerGlobalScope.h
@@ -43,6 +43,7 @@
 #include "platform/network/ContentSecurityPolicyParsers.h"
 #include "wtf/Assertions.h"
 #include "wtf/HashMap.h"
+#include "wtf/ListHashSet.h"
 #include "wtf/OwnPtr.h"
 #include "wtf/PassRefPtr.h"
 #include "wtf/RefCounted.h"
@@ -54,6 +55,7 @@ namespace blink {
 class ConsoleMessage;
 class ConsoleMessageStorage;
 class ExceptionState;
+class V8AbstractEventListener;
 class WorkerClients;
 class WorkerConsole;
 class WorkerInspectorController;
@@ -141,6 +143,9 @@ public:
 
     bool isSecureContext(String& errorMessage, const SecureContextCheck = StandardSecureContextCheck) const override;
 
+    void registerEventListener(V8AbstractEventListener*);
+    void deregisterEventListener(V8AbstractEventListener*);
+
     DECLARE_VIRTUAL_TRACE();
 
 protected:
@@ -200,6 +205,7 @@ private:
 
     unsigned long m_workerExceptionUniqueIdentifier;
     WillBeHeapHashMap<unsigned long, RefPtrWillBeMember<ConsoleMessage>> m_pendingMessages;
+    WillBeHeapListHashSet<RefPtrWillBeMember<V8AbstractEventListener>> m_eventListeners;
 };
 
 DEFINE_TYPE_CASTS(WorkerGlobalScope, ExecutionContext, context, context->isWorkerGlobalScope(), context.isWorkerGlobalScope());