Track reasons for |Node::SetNeedsStyleRecalc|

Source/core/rendering/RenderObject.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2000 Dirk Mueller (mueller@kde.org)
  *           (C) 2004 Allan Sandfeld Jensen (kde@carewolf.com)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2011 Apple Inc. All rights reserved.
  * Copyright (C) 2009 Google Inc. All rights reserved.
  * Copyright (C) 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  *
  * This library is free software; you can redistribute it and/or
@@ skipping 2819 matching lines @@
 {
     return createPositionWithAffinity(caretMinOffset(), DOWNSTREAM);
 }
 
 void RenderObject::updateDragState(bool dragOn)
 {
     bool valueChanged = (dragOn != isDragging());
     setIsDragging(dragOn);
     if (valueChanged && node()) {
         if (node()->isElementNode() && toElement(node())->childrenOrSiblingsAffectedByDrag())
-            node()->setNeedsStyleRecalc(SubtreeStyleChange);
+            node()->setNeedsStyleRecalc(StyleRecalcDueToDrag, SubtreeStyleChange);
         else if (style()->affectedByDrag())
-            node()->setNeedsStyleRecalc(LocalStyleChange);
+            node()->setNeedsStyleRecalc(StyleRecalcDueToDrag, LocalStyleChange);
     }
     for (RenderObject* curr = slowFirstChild(); curr; curr = curr->nextSibling())
         curr->updateDragState(dragOn);
 }
 
 CompositingState RenderObject::compositingState() const
 {
     return hasLayer() ? toRenderLayerModelObject(this)->layer()->compositingState() : NotComposited;
 }
 
@@ skipping 593 matching lines @@
 {
     if (object1) {
         const blink::RenderObject* root = object1;
         while (root->parent())
             root = root->parent();
         root->showRenderTreeAndMark(object1, "*", object2, "-", 0);
     }
 }
 
 #endif