SVG objects with same idrefs conflict when under different shadow root

third_party/WebKit/Source/core/svg/SVGElement.h

 /*
  * Copyright (C) 2004, 2005, 2006, 2008 Nikolas Zimmermann <zimmermann@kde.org>
  * Copyright (C) 2004, 2005, 2006 Rob Buis <buis@kde.org>
  * Copyright (C) 2009, 2014 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 40 matching lines @@
   DEFINE_WRAPPERTYPEINFO();
 
  public:
   ~SVGElement() override;
   void attachLayoutTree(const AttachContext&) override;
   void detachLayoutTree(const AttachContext&) override;
 
   int tabIndex() const override;
   bool supportsFocus() const override { return false; }
 
+  // The TreeScope this element should resolve id's against. This differs from
+  // the regular Node::treeScope() by taking <use> into account.
+  TreeScope& treeScopeForIdResolution() const;
+
   bool isOutermostSVGSVGElement() const;
 
   bool hasTagName(const SVGQualifiedName& name) const {
     return hasLocalName(name.localName());
   }
 
   String title() const override;
   bool hasRelativeLengths() const {
     return !m_elementsWithRelativeLengths.isEmpty();
   }
@@ skipping 259 matching lines @@
   inline bool isElementOfType<const thisType>(const SVGElement& element) { \
     return is##thisType(element);                                          \
   }                                                                        \
   DEFINE_ELEMENT_TYPE_CASTS_WITH_FUNCTION(thisType)
 
 }  // namespace blink
 
 #include "core/SVGElementTypeHelpers.h"
 
 #endif  // SVGElement_h