Remove all members in ScopedStyleTree for preparing class removal

Source/core/dom/DocumentStyleSheetCollection.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2001 Dirk Mueller (mueller@kde.org)
  *           (C) 2006 Alexey Proskuryakov (ap@webkit.org)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2012 Apple Inc. All rights reserved.
  * Copyright (C) 2008, 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  * Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies)
  * Copyright (C) 2013 Google Inc. All rights reserved.
  *
@@ skipping 89 matching lines @@
     analyzeStyleSheetChange(updateMode, collection, change);
 
     if (change.styleResolverUpdateType == Reconstruct) {
         engine->clearMasterResolver();
         // FIMXE: The following depends on whether StyleRuleFontFace was modified or not.
         // No need to always-clear font cache.
         engine->clearFontCache();
     } else if (StyleResolver* styleResolver = engine->resolver()) {
         if (change.styleResolverUpdateType != Additive) {
             ASSERT(change.styleResolverUpdateType == Reset);
-            styleResolver->resetAuthorStyle(&m_treeScope.rootNode());
+            styleResolver->resetAuthorStyle(m_treeScope);
             engine->removeFontFaceRules(change.fontFaceRulesToRemove);
             styleResolver->removePendingAuthorStyleSheets(m_activeAuthorStyleSheets);
             styleResolver->lazyAppendAuthorStyleSheets(0, collection.activeAuthorStyleSheets());
         } else {
             styleResolver->lazyAppendAuthorStyleSheets(m_activeAuthorStyleSheets.size(), collection.activeAuthorStyleSheets());
         }
     }
     if (change.requiresFullStyleRecalc)
         document().setNeedsStyleRecalc(SubtreeStyleChange);
 
     collection.swap(*this);
 
     updateUsesRemUnits();
 }
 
 }