Oilpan: Remove raw pointer to ExecutionContext from WorkerInspectorProxy

Source/core/workers/WorkerInspectorProxy.h

Index: Source/core/workers/WorkerInspectorProxy.h
diff --git a/Source/core/workers/WorkerInspectorProxy.h b/Source/core/workers/WorkerInspectorProxy.h
index 31ceee807b1cf3eb1733cdae62c69c64a4bc17f6..81bab2fb868ea2619409fd248589ce0c4caf2977 100644
--- a/Source/core/workers/WorkerInspectorProxy.h
+++ b/Source/core/workers/WorkerInspectorProxy.h
@@ -6,6 +6,7 @@
 #define WorkerInspectorProxy_h
 
 #include "core/CoreExport.h"
+#include "platform/heap/Handle.h"
 #include "public/platform/WebThread.h"
 #include "wtf/Forward.h"
 
@@ -19,17 +20,19 @@ class WorkerThread;
 
 // A proxy for talking to the worker inspector on the worker thread.
 // All of these methods should be called on the main thread.
-class CORE_EXPORT WorkerInspectorProxy final {
+class CORE_EXPORT WorkerInspectorProxy final : public NoBaseWillBeGarbageCollectedFinalized<WorkerInspectorProxy> {
 public:
-    static PassOwnPtr<WorkerInspectorProxy> create();
+    static PassOwnPtrWillBeRawPtr<WorkerInspectorProxy> create();
 
     ~WorkerInspectorProxy();
+    DECLARE_TRACE();
 
-    class PageInspector {
+    class PageInspector : public NoBaseWillBeGarbageCollectedFinalized<PageInspector> {
     public:
         virtual ~PageInspector() { }
         virtual void dispatchMessageFromWorker(const String&) = 0;
         virtual void workerConsoleAgentEnabled(WorkerGlobalScopeProxy*) = 0;
+        DEFINE_INLINE_VIRTUAL_TRACE() { }
     };
 
     void workerThreadCreated(ExecutionContext*, WorkerThread*, const KURL&);
@@ -51,8 +54,8 @@ private:
     void addDebuggerTaskForWorker(const WebTraceLocation&, PassOwnPtr<WebThread::Task>);
 
     WorkerThread* m_workerThread;

[haraken, 2015/07/30 07:47:32]

This raw pointer would be safe since the m_workerThread is explicitly cleared in
workerThreadTerminated().

-    ExecutionContext* m_executionContext;
-    WorkerInspectorProxy::PageInspector* m_pageInspector;
+    RawPtrWillBeMember<ExecutionContext> m_executionContext;
+    RawPtrWillBeMember<WorkerInspectorProxy::PageInspector> m_pageInspector;
     WorkerGlobalScopeProxy* m_workerGlobalScopeProxy;

[haraken, 2015/07/30 07:47:32]

I guess this pointer has a risk of becoming a stale pointer if:

1) WorkerGlobalScopeProxy gets destroyed.
2) GC is triggered and the WorkerInspectorProxy gets collected.

Between 1) and 2), WorkerInspectorProxy::m_workerGlobalScopeProxy can be stale.
I think you need to call:

   m_workerInspectorProxy->setWorkerGlobalScopeProxy(nullptr);

in WorkerMessagingProxy's destructor.

[keishi, 2015/08/03 09:35:56]

Done.

 };