Avoid leaking ThreadingPrimitives.h from StackStats.h when collection is off.

Source/core/rendering/RenderTableSection.cpp

 /*
  * Copyright (C) 1997 Martin Jones (mjones@kde.org)
  *           (C) 1997 Torben Weis (weis@kde.org)
  *           (C) 1998 Waldo Bastian (bastian@kde.org)
  *           (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  * Copyright (C) 2003, 2004, 2005, 2006, 2008, 2009, 2010 Apple Inc. All rights reserved.
  * Copyright (C) 2006 Alexey Proskuryakov (ap@nypop.com)
  *
  * This library is free software; you can redistribute it and/or
@@ skipping 582 matching lines @@
 
     ASSERT(!needsLayout());
 
     statePusher.pop();
 
     return m_rowPos[m_grid.size()];
 }
 
 void RenderTableSection::layout()
 {
-    StackStats::LayoutCheckPoint layoutCheckPoint;
     ASSERT(needsLayout());
     ASSERT(!needsCellRecalc());
     ASSERT(!table()->needsSectionRecalc());
 
     // addChild may over-grow m_grid but we don't want to throw away the memory too early as addChild
     // can be called in a loop (e.g during parsing). Doing it now ensures we have a stable-enough structure.
     m_grid.shrinkToFit();
 
     LayoutStateMaintainer statePusher(view(), this, locationOffset(), style()->isFlippedBlocksWritingMode());
 
@@ skipping 1070 matching lines @@
     if (!style()->isLeftToRightDirection())
         cellLocation.setX(table()->columnPositions()[table()->numEffCols()] - table()->columnPositions()[table()->colToEffCol(cell->col() + cell->colSpan())] + horizontalBorderSpacing);
     else
         cellLocation.setX(table()->columnPositions()[effectiveColumn] + horizontalBorderSpacing);
 
     cell->setLogicalLocation(cellLocation);
     view()->addLayoutDelta(oldCellLocation - cell->location());
 }
 
 } // namespace WebCore