Tried using CrossThreadPersistent for workerDebuggerAgents

Source/core/inspector/PageConsoleAgent.cpp

Index: Source/core/inspector/PageConsoleAgent.cpp
diff --git a/Source/core/inspector/PageConsoleAgent.cpp b/Source/core/inspector/PageConsoleAgent.cpp
index dfa5c70898f555637fd881f7c5bc74a2f3f79b17..2540f7454580709d813bac90912f5b0ffdcd9e83 100644
--- a/Source/core/inspector/PageConsoleAgent.cpp
+++ b/Source/core/inspector/PageConsoleAgent.cpp
@@ -47,7 +47,15 @@ PageConsoleAgent::PageConsoleAgent(InjectedScriptManager* injectedScriptManager,
 
 PageConsoleAgent::~PageConsoleAgent()
 {
-    m_inspectorDOMAgent = 0;
+#if !ENABLE(OILPAN)
+    m_inspectorDOMAgent = nullptr;
+#endif
+}
+
+void PageConsoleAgent::trace(Visitor* visitor)
+{
+    visitor->trace(m_inspectorDOMAgent);
+    InspectorConsoleAgent::trace(visitor);
 }
 
 void PageConsoleAgent::clearMessages(ErrorString* errorString)