Improve RAII of StyleResolverState.

Source/core/css/resolver/FontBuilder.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.
  * Copyright (C) 2013 Google 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.
  *
@@ skipping 42 matching lines @@
     ~FontDescriptionChangeScope()
     {
         m_fontBuilder->didChangeFontParameters(m_fontBuilder->m_style->setFontDescription(m_fontDescription));
     }
 
 private:
     RawPtrWillBeMember<FontBuilder> m_fontBuilder;
     FontDescription m_fontDescription;
 };
 
-FontBuilder::FontBuilder(const Document& document)
+FontBuilder::FontBuilder(const Document& document, RenderStyle* style)
     : m_document(document)
-    , m_style(nullptr)
+    , m_style(style)
     , m_fontDirty(false)
 {
     ASSERT(document.frame());
 }
 
 void FontBuilder::setInitial(float effectiveZoom)
 {
     ASSERT(m_document.settings());
     if (!m_document.settings())
         return;
@@ skipping 315 matching lines @@
     FontOrientation fontOrientation;
     NonCJKGlyphOrientation glyphOrientation;
     getFontAndGlyphOrientation(documentStyle, fontOrientation, glyphOrientation);
     fontDescription.setOrientation(fontOrientation);
     fontDescription.setNonCJKGlyphOrientation(glyphOrientation);
     documentStyle->setFontDescription(fontDescription);
     documentStyle->font().update(fontSelector);
 }
 
 }