SVG objects with same idrefs conflict when under different shadow root

third_party/WebKit/Source/core/dom/TreeScope.cpp

 /*
  * Copyright (C) 2011 Google Inc. All Rights Reserved.
  * Copyright (C) 2012 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
@@ skipping 31 matching lines @@
 #include "core/events/EventPath.h"
 #include "core/frame/FrameView.h"
 #include "core/frame/LocalFrame.h"
 #include "core/html/HTMLAnchorElement.h"
 #include "core/html/HTMLFrameOwnerElement.h"
 #include "core/html/HTMLMapElement.h"
 #include "core/layout/HitTestResult.h"
 #include "core/layout/api/LayoutViewItem.h"
 #include "core/page/FocusController.h"
 #include "core/page/Page.h"
+#include "core/svg/SVGTreeScopeResources.h"
 #include "wtf/Vector.h"
 
 namespace blink {
 
 using namespace HTMLNames;
 
 TreeScope::TreeScope(ContainerNode& rootNode, Document& document)
     : m_rootNode(&rootNode),
       m_document(&document),
       m_parentTreeScope(&document),
@@ skipping 228 matching lines @@
 
   HitTestRequest request(HitTestRequest::ReadOnly | HitTestRequest::Active |
                          HitTestRequest::ListBased |
                          HitTestRequest::PenetratingList);
   HitTestResult result(request, hitPoint);
   document.layoutViewItem().hitTest(result);
 
   return elementsFromHitTestResult(result);
 }
 
+SVGTreeScopeResources& TreeScope::ensureSVGTreeScopedResources() {
+  if (!m_svgTreeScopedResources)
+    m_svgTreeScopedResources = new SVGTreeScopeResources(this);
+  return *m_svgTreeScopedResources;
+}
+
 DOMSelection* TreeScope::getSelection() const {
   if (!rootNode().document().frame())
     return nullptr;
 
   if (m_selection)
     return m_selection.get();
 
   // FIXME: The correct selection in Shadow DOM requires that Position can have
   // a ShadowRoot as a container.  See
   // https://bugs.webkit.org/show_bug.cgi?id=82697
@@ skipping 208 matching lines @@
 DEFINE_TRACE(TreeScope) {
   visitor->trace(m_rootNode);
   visitor->trace(m_document);
   visitor->trace(m_parentTreeScope);
   visitor->trace(m_idTargetObserverRegistry);
   visitor->trace(m_selection);
   visitor->trace(m_elementsById);
   visitor->trace(m_imageMapsByName);
   visitor->trace(m_scopedStyleResolver);
   visitor->trace(m_radioButtonGroupScope);
+  visitor->trace(m_svgTreeScopedResources);
 }
 
 }  // namespace blink