Oilpan: Remove OffHeapCollectionTrait

Source/core/events/EventPath.cpp

 /*
  * Copyright (C) 2013 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.
  *     * Neither the name of Google Inc. nor the names of its
@@ skipping 329 matching lines @@
 #if ENABLE(ASSERT)
 void EventPath::checkReachability(TreeScope& treeScope, TouchList& touchList)
 {
     for (size_t i = 0; i < touchList.length(); ++i)
         ASSERT(touchList.item(i)->target()->toNode()->treeScope().isInclusiveOlderSiblingShadowRootOrAncestorTreeScopeOf(treeScope));
 }
 #endif
 
 DEFINE_TRACE(EventPath)
 {
+#if ENABLE(OILPAN)
     visitor->trace(m_nodeEventContexts);
     visitor->trace(m_node);
     visitor->trace(m_event);
     visitor->trace(m_treeScopeEventContexts);
     visitor->trace(m_windowEventContext);
+#endif
 }
 
 } // namespace