Tried using CrossThreadPersistent for workerDebuggerAgents

Source/core/inspector/InspectorHeapProfilerAgent.h

Index: Source/core/inspector/InspectorHeapProfilerAgent.h
diff --git a/Source/core/inspector/InspectorHeapProfilerAgent.h b/Source/core/inspector/InspectorHeapProfilerAgent.h
index 8d18cac5d1b7389bee5de9926c9cf0aaa0fcdb2a..779f35afb1f75f171a1a43bf74f63005ed2b6424 100644
--- a/Source/core/inspector/InspectorHeapProfilerAgent.h
+++ b/Source/core/inspector/InspectorHeapProfilerAgent.h
@@ -49,10 +49,12 @@ class ScriptHeapSnapshot;
 typedef String ErrorString;
 
 class InspectorHeapProfilerAgent FINAL : public InspectorBaseAgent<InspectorHeapProfilerAgent>, public InspectorBackendDispatcher::HeapProfilerCommandHandler {
-    WTF_MAKE_NONCOPYABLE(InspectorHeapProfilerAgent); WTF_MAKE_FAST_ALLOCATED;
+    WTF_MAKE_NONCOPYABLE(InspectorHeapProfilerAgent);
+    WTF_MAKE_FAST_ALLOCATED_WILL_BE_REMOVED;
 public:
-    static PassOwnPtr<InspectorHeapProfilerAgent> create(InjectedScriptManager*);
+    static PassOwnPtrWillBeRawPtr<InspectorHeapProfilerAgent> create(InjectedScriptManager*);
     virtual ~InspectorHeapProfilerAgent();
+    virtual void trace(Visitor*) OVERRIDE;
 
     virtual void collectGarbage(ErrorString*) OVERRIDE;
 
@@ -85,7 +87,7 @@ private:
     InjectedScriptManager* m_injectedScriptManager;
     InspectorFrontend::HeapProfiler* m_frontend;
     unsigned m_nextUserInitiatedHeapSnapshotNumber;
-    OwnPtr<HeapStatsUpdateTask> m_heapStatsUpdateTask;
+    OwnPtrWillBeMember<HeapStatsUpdateTask> m_heapStatsUpdateTask;
 };
 
 } // namespace WebCore