Use TreeScope::completeURL and baseURL instead of the Document versions

Source/core/svg/SVGUseElement.cpp

Index: Source/core/svg/SVGUseElement.cpp
diff --git a/Source/core/svg/SVGUseElement.cpp b/Source/core/svg/SVGUseElement.cpp
index 9bdf713ca431656f4cddae0971b08de71e86df00..4fe238b2714df4fb7c58f305e1e2353fab28a5b7 100644
--- a/Source/core/svg/SVGUseElement.cpp
+++ b/Source/core/svg/SVGUseElement.cpp
@@ -223,7 +223,7 @@ void SVGUseElement::svgAttributeChanged(const QualifiedName& attrName)
     if (SVGURIReference::isKnownAttribute(attrName)) {
         bool isExternalReference = isExternalURIReference(hrefCurrentValue(), document());
         if (isExternalReference) {
-            KURL url = document().completeURL(hrefCurrentValue());
+            KURL url = treeScope().completeURL(hrefCurrentValue());
             if (url.hasFragmentIdentifier()) {
                 FetchRequest request(ResourceRequest(url.string()), localName());
                 setDocumentResource(document().fetcher()->fetchSVGDocument(request));