Don't transfer viewport to an invalid/dirty <use> instance

Source/core/svg/SVGUseElement.h

Index: Source/core/svg/SVGUseElement.h
diff --git a/Source/core/svg/SVGUseElement.h b/Source/core/svg/SVGUseElement.h
index 647b59ee3952ae1d04e8bd95e2bcbc76cd8d5a1b..280bad76c26555f235e8a12530deeda9c0c2e646 100644
--- a/Source/core/svg/SVGUseElement.h
+++ b/Source/core/svg/SVGUseElement.h
@@ -76,16 +76,17 @@ private:
 
     LayoutObject* createLayoutObject(const ComputedStyle&) override;
 
-    void clearResourceReferences();
-    void buildShadowAndInstanceTree(SVGElement* target);
-
     void scheduleShadowTreeRecreation();
+    void cancelShadowTreeRecreation();
     bool haveLoadedRequiredResources() override { return !isStructurallyExternal() || m_haveFiredLoadEvent; }
 
     bool selfHasRelativeLengths() const override;
 
     // Instance tree handling
+    void buildShadowAndInstanceTree(SVGElement* target);
+    void clearInstanceRoot();
     bool buildShadowTree(SVGElement* target, SVGElement* targetInstance, bool foundUse);
+    void clearShadowTree();
     bool hasCycleUseReferencing(SVGUseElement*, ContainerNode* targetInstance, SVGElement*& newTarget);
     bool expandUseElementsInShadowTree(SVGElement*);
     void expandSymbolElementsInShadowTree(SVGElement*);