SVG object with same idrefs get conflicted even they are under different shadow root

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

+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef SVGTreeScopeResources_h
+#define SVGTreeScopeResources_h
+
+#include "platform/geometry/FloatPoint.h"
+#include "platform/heap/Handle.h"
+#include "wtf/Forward.h"
+#include "wtf/HashMap.h"
+#include "wtf/HashSet.h"
+#include "wtf/text/AtomicStringHash.h"
+
+
+namespace blink {
+class Element;
+class TreeScope;
+class LayoutSVGResourceContainer;
+
+class SVGTreeScopeResources : public GarbageCollectedFinalized<SVGTreeScopeResources> {
+    WTF_MAKE_NONCOPYABLE(SVGTreeScopeResources);
+public:
+    typedef HeapHashSet<Member<Element>> SVGPendingElements;
+    explicit SVGTreeScopeResources(TreeScope*);
+    ~SVGTreeScopeResources();
+    void addResource(const AtomicString& id, LayoutSVGResourceContainer*);
+    void removeResource(const AtomicString& id);
+    LayoutSVGResourceContainer* resourceById(const AtomicString& id) const;
+
+    // This HashMap contains a list of pending resources. Pending resources, are such
+    // which are referenced by any object in the SVG document, but do NOT exist yet.
+    // For instance, dynamically build gradients / patterns / clippers...
+    void addPendingResource(const AtomicString& id, Element*);
+    bool hasPendingResource(const AtomicString& id) const;
+    bool isElementPendingResources(Element*) const;
+    bool isElementPendingResource(Element*, const AtomicString& id) const;
+    void clearHasPendingResourcesIfPossible(Element*);
+    void removeElementFromPendingResources(Element*);
+    SVGPendingElements* removePendingResource(const AtomicString& id);
+
+    // The following two functions are used for scheduling a pending resource to be removed.
+    void markPendingResourcesForRemoval(const AtomicString&);
+    Element* removeElementFromPendingResourcesForRemoval(const AtomicString&);
+
+    DECLARE_TRACE();
+private:
+    Member<TreeScope> m_treeScope;
+    HashMap<AtomicString, LayoutSVGResourceContainer*> m_resources;
+    HeapHashMap<AtomicString, Member<SVGPendingElements>> m_pendingResources; // Resources that are pending.
+    HeapHashMap<AtomicString, Member<SVGPendingElements>> m_pendingResourcesForRemoval; // Resources that are pending and scheduled for removal.
+
+    SVGPendingElements* removePendingResourceForRemoval(const AtomicString&);
+    };
+}
+#endif // SVGTreeScopeResources_h