Oilpan: Remove raw pointer to InProcessWorkerBase from WorkerMessagingProxy

Source/core/workers/WorkerMessagingProxy.cpp

Index: Source/core/workers/WorkerMessagingProxy.cpp
diff --git a/Source/core/workers/WorkerMessagingProxy.cpp b/Source/core/workers/WorkerMessagingProxy.cpp
index 228b63f2c06ab3701369fcccec7e8befc0ea8e05..2305a09d16256ec913558b9d830deea28c3d90d7 100644
--- a/Source/core/workers/WorkerMessagingProxy.cpp
+++ b/Source/core/workers/WorkerMessagingProxy.cpp
@@ -81,13 +81,18 @@ WorkerMessagingProxy::WorkerMessagingProxy(InProcessWorkerBase* workerObject, Pa
     ASSERT((m_executionContext->isDocument() && isMainThread())
         || (m_executionContext->isWorkerGlobalScope() && toWorkerGlobalScope(m_executionContext.get())->thread()->isCurrentThread()));
     m_workerInspectorProxy->setWorkerGlobalScopeProxy(this);
+#if ENABLE(OILPAN)
+    m_keepAlive = adoptPtr(new Persistent<WorkerMessagingProxy>(this));
+#endif
 }
 
 WorkerMessagingProxy::~WorkerMessagingProxy()
 {
     ASSERT(!m_workerObject);
+#if !ENABLE(OILPAN)
     ASSERT((m_executionContext->isDocument() && isMainThread())
         || (m_executionContext->isWorkerGlobalScope() && toWorkerGlobalScope(m_executionContext.get())->thread()->isCurrentThread()));
+#endif
     if (m_loaderProxy)
         m_loaderProxy->detachProvider(this);
 }
@@ -222,8 +227,13 @@ void WorkerMessagingProxy::workerThreadTerminated()
     m_askedToTerminate = true;
     m_workerThread = nullptr;
     terminateInternally();
-    if (m_mayBeDestroyed)
+    if (m_mayBeDestroyed) {
+#if ENABLE(OILPAN)
+        m_keepAlive.release();
+#else
         delete this;
+#endif
+    }
 }
 
 void WorkerMessagingProxy::terminateWorkerGlobalScope()
@@ -292,4 +302,19 @@ void WorkerMessagingProxy::terminateInternally()
         frame->console().adoptWorkerMessagesAfterTermination(this);
 }
 
+void WorkerMessagingProxy::clearWeakMembers(Visitor* visitor)
+{
+    if (Heap::isHeapObjectAlive(m_workerObject))
+        return;
+    workerObjectDestroyed();

[haraken, 2015/07/30 11:46:31]

It is not nice to call workerObjectDestroyed() in weak processing, since the
weak processing is not called if the WorkerMessagingProxy and the
InProcessWorkerBase die at the same time.

I think we should call workerObjectDestroyed() in the pre-finalizer of
InProcessWorkerBase. Then workerObjectDestroyed() will be unconditionally called
before the InProcessWorkerBase gets destructed.

+}
+
+DEFINE_TRACE(WorkerMessagingProxy)
+{
+    visitor->trace(m_executionContext);
+    visitor->trace(m_workerClients);
+    visitor->template registerWeakMembers<WorkerMessagingProxy, &WorkerMessagingProxy::clearWeakMembers>(this);
+    WorkerGlobalScopeProxy::trace(visitor);
+}
+
 } // namespace blink