Replace cloneNodeAndAssociate with Element::cloneElementWithChildren

third_party/WebKit/Source/core/svg/SVGUseElement.cpp

Index: third_party/WebKit/Source/core/svg/SVGUseElement.cpp
diff --git a/third_party/WebKit/Source/core/svg/SVGUseElement.cpp b/third_party/WebKit/Source/core/svg/SVGUseElement.cpp
index 0293b9e0379b059380a1cb89e820ab4545731fc0..46e52916022ba0e0e07e88645fd129e80e90cf68 100644
--- a/third_party/WebKit/Source/core/svg/SVGUseElement.cpp
+++ b/third_party/WebKit/Source/core/svg/SVGUseElement.cpp
@@ -356,19 +356,16 @@ void SVGUseElement::buildPendingResource()
     ASSERT(!m_needsShadowTreeRecreation);
 }
 
-static PassRefPtrWillBeRawPtr<Node> cloneNodeAndAssociate(Node& toClone)
-{
-    RefPtrWillBeRawPtr<Node> clone = toClone.cloneNode(false);
-    if (!clone->isSVGElement())
-        return clone.release();
-
-    SVGElement& svgElement = toSVGElement(toClone);
-    ASSERT(!svgElement.correspondingElement());
-    toSVGElement(clone.get())->setCorrespondingElement(&svgElement);
-    TrackExceptionState exceptionState;
-    for (RefPtrWillBeRawPtr<Node> node = toClone.firstChild(); node && !exceptionState.hadException(); node = node->nextSibling())
-        clone->appendChild(cloneNodeAndAssociate(*node), exceptionState);
-    return clone.release();
+static void associateCorrespondingElements(SVGElement& targetRoot, SVGElement& instanceRoot)
+{
+    auto targetRange = Traversal<SVGElement>::inclusiveDescendantsOf(targetRoot);
+    auto targetIterator = targetRange.begin();
+    for (SVGElement& instance : Traversal<SVGElement>::inclusiveDescendantsOf(instanceRoot)) {
+        ASSERT(!instance.correspondingElement());
+        instance.setCorrespondingElement(&*targetIterator);
+        ++targetIterator;
+    }
+    ASSERT(!(targetIterator != targetRange.end()));

[Stephen Chennney, 2016/03/03 16:42:01]

So we have a != operator but no == operator? Interesting.

[fs, 2016/03/03 16:59:07]

Yeah, I guess it's heavily tailored to the range-based for usage.

 }
 
 void SVGUseElement::buildShadowAndInstanceTree(SVGElement& target)
@@ -629,14 +626,14 @@ bool SVGUseElement::expandUseElementsInShadowTree()
         moveChildrenToReplacementElement(*use, *cloneParent);
 
         if (target) {
-            RefPtrWillBeRawPtr<Node> newChild = cloneNodeAndAssociate(*target);
-            ASSERT(newChild->isSVGElement());
-            transferUseWidthAndHeightIfNeeded(*use, toSVGElement(*newChild), *target);
-            cloneParent->appendChild(newChild.release());
+            RefPtrWillBeRawPtr<Element> instanceRoot = target->cloneElementWithChildren();
+            ASSERT(instanceRoot->isSVGElement());
+            associateCorrespondingElements(*target, toSVGElement(*instanceRoot));
+            transferUseWidthAndHeightIfNeeded(*use, toSVGElement(*instanceRoot), *target);
+            removeDisallowedElementsFromSubtree(toSVGElement(*instanceRoot));
+            cloneParent->appendChild(instanceRoot.release());
         }
 
-        removeDisallowedElementsFromSubtree(*cloneParent);
-
         RefPtrWillBeRawPtr<SVGElement> replacingElement(cloneParent.get());
 
         // Replace <use> with referenced content.