Tried using CrossThreadPersistent for workerDebuggerAgents

Source/core/inspector/InspectorPageAgent.h

Index: Source/core/inspector/InspectorPageAgent.h
diff --git a/Source/core/inspector/InspectorPageAgent.h b/Source/core/inspector/InspectorPageAgent.h
index 97820c8725114f3aad59b4bd7f89de9938fc5f2c..603e0190d506969314922a6312eb79757f64c936 100644
--- a/Source/core/inspector/InspectorPageAgent.h
+++ b/Source/core/inspector/InspectorPageAgent.h
@@ -76,7 +76,7 @@ public:
         OtherResource
     };
 
-    static PassOwnPtr<InspectorPageAgent> create(Page*, InjectedScriptManager*, InspectorClient*, InspectorOverlay*);
+    static PassOwnPtrWillBeRawPtr<InspectorPageAgent> create(Page*, InjectedScriptManager*, InspectorClient*, InspectorOverlay*);
 
     // Settings overrides.
     void setTextAutosizingEnabled(bool);
@@ -161,6 +161,8 @@ public:
     bool deviceMetricsOverrideEnabled();
     static DocumentLoader* assertDocumentLoader(ErrorString*, LocalFrame*);
 
+    virtual void trace(Visitor*) OVERRIDE;
+
 private:
     static void resourceContent(ErrorString*, LocalFrame*, const KURL&, String* result, bool* base64Encoded);
 
@@ -175,7 +177,7 @@ private:
 
     PassRefPtr<TypeBuilder::Page::Frame> buildObjectForFrame(LocalFrame*);
     PassRefPtr<TypeBuilder::Page::FrameResourceTree> buildObjectForFrameTree(LocalFrame*);
-    Page* m_page;
+    RawPtrWillBeMember<Page> m_page;
     InjectedScriptManager* m_injectedScriptManager;
     InspectorClient* m_client;
     InspectorFrontend::Page* m_frontend;