[oilpan]: Remove support for tracing off-heap hashmaps.

Source/core/dom/ScriptRunner.cpp

 /*
  * Copyright (C) 2010 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:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 117 matching lines @@
     for (size_t i = 0; i < size; ++i) {
         ScriptResource* resource = scripts[i].resource();
         RefPtrWillBeRawPtr<Element> element = scripts[i].releaseElementAndClear();
         toScriptLoaderIfPossible(element.get())->execute(resource);
         m_document->decrementLoadEventDelayCount();
     }
 }
 
 void ScriptRunner::trace(Visitor* visitor)
 {
+#if ENABLE(OILPAN)
     visitor->trace(m_document);
     visitor->trace(m_scriptsToExecuteInOrder);
     visitor->trace(m_scriptsToExecuteSoon);
     visitor->trace(m_pendingAsyncScripts);
+#endif
 }
 
 }