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

Source/core/rendering/RenderRubyRun.cpp

 /*
  * Copyright (C) 2009 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 198 matching lines @@
     ASSERT(parentRuby && parentRuby->isRuby());
     RenderRubyRun* rr = new RenderRubyRun();
     rr->setDocumentForAnonymous(parentRuby->document());
     RefPtr<RenderStyle> newStyle = RenderStyle::createAnonymousStyleWithDisplay(parentRuby->style(), INLINE_BLOCK);
     rr->setStyle(newStyle.release());
     return rr;
 }
 
 RenderObject* RenderRubyRun::layoutSpecialExcludedChild(bool relayoutChildren, SubtreeLayoutScope& layoutScope)
 {
-    StackStats::LayoutCheckPoint layoutCheckPoint;
     // Don't bother positioning the RenderRubyRun yet.
     RenderRubyText* rt = rubyText();
     if (!rt)
         return 0;
     if (relayoutChildren)
         layoutScope.setChildNeedsLayout(rt);
     rt->layoutIfNeeded();
     return rt;
 }
 
@@ skipping 80 matching lines @@
     // We can overhang the ruby by no more than half the width of the neighboring text
     // and no more than half the font size.
     int halfWidthOfFontSize = rubyText->style(firstLine)->fontSize() / 2;
     if (startOverhang)
         startOverhang = min<int>(startOverhang, min<int>(toRenderText(startRenderer)->minLogicalWidth(), halfWidthOfFontSize));
     if (endOverhang)
         endOverhang = min<int>(endOverhang, min<int>(toRenderText(endRenderer)->minLogicalWidth(), halfWidthOfFontSize));
 }
 
 } // namespace WebCore