Tried using CrossThreadPersistent for workerDebuggerAgents

Source/core/inspector/InspectorHistory.cpp

 /*
  * Copyright (C) 2012 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 44 matching lines @@
 }
 
 InspectorHistory::Action::Action(const String& name) : m_name(name)
 {
 }
 
 InspectorHistory::Action::~Action()
 {
 }
 
+void InspectorHistory::Action::trace(Visitor* visitor)
+{
+}
+
 String InspectorHistory::Action::toString()
 {
     return m_name;
 }
 
 bool InspectorHistory::Action::isUndoableStateMark()
 {
     return false;
 }
 
 String InspectorHistory::Action::mergeId()
 {
     return "";
 }
 
-void InspectorHistory::Action::merge(PassRefPtr<Action>)
+void InspectorHistory::Action::merge(PassRefPtrWillBeRawPtr<Action>)
 {
 }
 
 InspectorHistory::InspectorHistory() : m_afterLastActionIndex(0) { }
 
-bool InspectorHistory::perform(PassRefPtr<Action> action, ExceptionState& exceptionState)
+bool InspectorHistory::perform(PassRefPtrWillBeRawPtr<Action> action, ExceptionState& exceptionState)
 {
     if (!action->perform(exceptionState))
         return false;
 
     if (!action->mergeId().isEmpty() && m_afterLastActionIndex > 0 && action->mergeId() == m_history[m_afterLastActionIndex - 1]->mergeId())
         m_history[m_afterLastActionIndex - 1]->merge(action);
     else {
         m_history.resize(m_afterLastActionIndex);
         m_history.append(action);
         ++m_afterLastActionIndex;
     }
     return true;
 }
 
 void InspectorHistory::markUndoableState()
 {
-    perform(adoptRef(new UndoableStateMark()), IGNORE_EXCEPTION);
+    perform(adoptRefWillBeNoop(new UndoableStateMark()), IGNORE_EXCEPTION);
 }
 
 bool InspectorHistory::undo(ExceptionState& exceptionState)
 {
     while (m_afterLastActionIndex > 0 && m_history[m_afterLastActionIndex - 1]->isUndoableStateMark())
         --m_afterLastActionIndex;
 
     while (m_afterLastActionIndex > 0) {
         Action* action = m_history[m_afterLastActionIndex - 1].get();
         if (!action->undo(exceptionState)) {
@@ skipping 25 matching lines @@
     }
     return true;
 }
 
 void InspectorHistory::reset()
 {
     m_afterLastActionIndex = 0;
     m_history.clear();
 }
 
+void InspectorHistory::trace(Visitor* visitor)
+{
+    visitor->trace(m_history);
+}
+
 } // namespace WebCore