Oilpan: fix build after r193519.

Source/core/dom/Position.cpp

 /*
  * Copyright (C) 2004, 2005, 2006, 2009 Apple 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 1353 matching lines @@
     for (const LayoutObject* r = m_anchorNode->layoutObject(); r; r = r->parent()) {
         if (r->isLayoutBlockFlow()) {
             primaryDirection = r->style()->direction();
             break;
         }
     }
 
     return primaryDirection;
 }
 
-DEFINE_TRACE(Position)
-{
-    visitor->trace(m_anchorNode);
-}
-
 template <typename Strategy>
 void PositionAlgorithm<Strategy>::debugPosition(const char* msg) const
 {
     static const char* const anchorTypes[] = {
         "OffsetInAnchor",
         "BeforeAnchor",
         "AfterAnchor",
         "BeforeChildren",
         "AfterChildren",
         "Invalid",
@@ skipping 81 matching lines @@
     pos.showTreeForThis();
 }
 
 void showTree(const blink::Position* pos)
 {
     if (pos)
         pos->showTreeForThis();
 }
 
 #endif