Clear StyleResolverState after each resolve.

Source/core/css/resolver/StyleResolverState.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  * Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
  * This library is distributed in the hope that it will be useful,
@@ skipping 29 matching lines @@
     NodeRenderingContext context(element);
     m_parentNode = context.parentNodeForRenderingAndStyle();
     m_distributedToInsertionPoint = context.insertionPoint();
     m_resetStyleInheritance = context.resetStyleInheritance();
 
     Node* documentElement = document()->documentElement();
     RenderStyle* documentStyle = document()->renderStyle();
     m_rootElementStyle = documentElement && element != documentElement ? documentElement->renderStyle() : documentStyle;
 }
 
+ScopedStyleResolution::ScopedStyleResolution(StyleResolverState* state, Document* document, Element* e, RenderStyle* parentStyle, RenderRegion* regionForStyling)
+    : m_state(state)
+{
+    m_state->initForStyleResolve(document, e, parentStyle, regionForStyling);
+}
+
+ScopedStyleResolution::~ScopedStyleResolution()
+{
+    m_state->clear();
+}
+
 void StyleResolverState::clear()
 {
     // FIXME: Use m_elementContent = ElementContext() instead.
     m_elementContext.deprecatedPartialClear();
 
+    m_style = 0;
     m_parentStyle = 0;
     m_regionForStyling = 0;
     m_elementStyleResources.clear();
 }
 
 void StyleResolverState::initForStyleResolve(Document* newDocument, Element* newElement, RenderStyle* parentStyle, RenderRegion* regionForStyling)
 {
     ASSERT(!element() || document() == newDocument);
     if (newElement != element()) {
         if (newElement)
@@ skipping 24 matching lines @@
     m_fontDirty = false;
 
     // FIXME: StyleResolverState is never passed between documents
     // so we should be able to do this initialization at StyleResolverState
     // createion time instead of now, correct?
     if (Page* page = newDocument->page())
         m_elementStyleResources.setDeviceScaleFactor(page->deviceScaleFactor());
 }
 
 } // namespace WebCore