Factor SVG root painter code into SVGRootPainter

Source/core/rendering/svg/RenderSVGRoot.h

 /*
  * Copyright (C) 2004, 2005, 2007 Nikolas Zimmermann <zimmermann@kde.org>
  * Copyright (C) 2004, 2005, 2007 Rob Buis <buis@kde.org>
  * Copyright (C) 2009 Google, Inc.  All rights reserved.
  * Copyright (C) 2009 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.
@@ skipping 26 matching lines @@
 
     bool isEmbeddedThroughSVGImage() const;
     bool isEmbeddedThroughFrameContainingSVGDocument() const;
 
     virtual void computeIntrinsicRatioInformation(FloatSize& intrinsicSize, double& intrinsicRatio) const override;
 
     // If you have a RenderSVGRoot, use firstChild or lastChild instead.
     void slowFirstChild() const WTF_DELETED_FUNCTION;
     void slowLastChild() const WTF_DELETED_FUNCTION;
 
+    RenderObject* firstChild() const { ASSERT(children() == virtualChildren()); return children()->firstChild(); }
+    RenderObject* lastChild() const { ASSERT(children() == virtualChildren()); return children()->lastChild(); }
+
     bool isLayoutSizeChanged() const { return m_isLayoutSizeChanged; }
     virtual void setNeedsBoundariesUpdate() override { m_needsBoundariesOrTransformUpdate = true; }
     virtual void setNeedsTransformUpdate() override { m_needsBoundariesOrTransformUpdate = true; }
 
     IntSize containerSize() const { return m_containerSize; }
     void setContainerSize(const IntSize& containerSize)
     {
         // SVGImage::draw() does a view layout prior to painting,
         // and we need that layout to know of the new size otherwise
         // the rendering may be incorrectly using the old size.
         if (m_containerSize != containerSize)
             setNeedsLayoutAndFullPaintInvalidation();
         m_containerSize = containerSize;
     }
 
     // localToBorderBoxTransform maps local SVG viewport coordinates to local CSS box coordinates.
     const AffineTransform& localToBorderBoxTransform() const { return m_localToBorderBoxTransform; }
     bool shouldApplyViewportClip() const;
 
+
+
 private:
-    RenderObject* firstChild() const { ASSERT(children() == virtualChildren()); return children()->firstChild(); }
-    RenderObject* lastChild() const { ASSERT(children() == virtualChildren()); return children()->lastChild(); }
-
     const RenderObjectChildList* children() const { return &m_children; }
     RenderObjectChildList* children() { return &m_children; }
 
     virtual RenderObjectChildList* virtualChildren() override { return children(); }
     virtual const RenderObjectChildList* virtualChildren() const override { return children(); }
 
     virtual const char* renderName() const override { return "RenderSVGRoot"; }
     virtual bool isOfType(RenderObjectType type) const override { return type == RenderObjectSVG || type == RenderObjectSVGRoot || RenderReplaced::isOfType(type); }
 
     virtual LayoutUnit computeReplacedLogicalWidth(ShouldComputePreferred  = ComputeActual) const override;
@@ skipping 42 matching lines @@
     bool m_isLayoutSizeChanged : 1;
     bool m_needsBoundariesOrTransformUpdate : 1;
     bool m_hasBoxDecorationBackground : 1;
 };
 
 DEFINE_RENDER_OBJECT_TYPE_CASTS(RenderSVGRoot, isSVGRoot());
 
 } // namespace blink
 
 #endif // RenderSVGRoot_h