Updated SVGListPropertyHelper as per SVG2 Spec

Source/core/svg/SVGTransformList.cpp

Index: Source/core/svg/SVGTransformList.cpp
diff --git a/Source/core/svg/SVGTransformList.cpp b/Source/core/svg/SVGTransformList.cpp
index 652fa55f04f36a2bd0c0d6af9d1951d37fdcd6a6..6e17b4f599995bb274759304ab0c9bc5e0c94f44 100644
--- a/Source/core/svg/SVGTransformList.cpp
+++ b/Source/core/svg/SVGTransformList.cpp
@@ -351,4 +351,52 @@ float SVGTransformList::calculateDistance(PassRefPtrWillBeRawPtr<SVGPropertyBase
     return SVGTransformDistance(at(0), toList->at(0)).distance();
 }
 
+PassRefPtrWillBeRawPtr<SVGTransform>SVGTransformList::initialize(PassRefPtrWillBeRawPtr<SVGTransform> passNewItem)
+{
+    RefPtrWillBeRawPtr<SVGTransform> newItem = passNewItem;
+
+    // SVG2-Draft Spec: If newItem is already in a list, then a new SVGTransform object is created with the same values as newItem and this item is inserted into the list.
+    // Otherwise, newItem itself is inserted into the list.
+    if (newItem->ownerList())
+        return Base::initialize(newItem->clone());
+
+    return Base::initialize(newItem);
+}
+
+PassRefPtrWillBeRawPtr<SVGTransform> SVGTransformList::appendItem(PassRefPtrWillBeRawPtr<SVGTransform> passNewItem)
+{
+    RefPtrWillBeRawPtr<SVGTransform> newItem = passNewItem;
+
+    // SVG2-Draft Spec: If newItem is already in a list, then a new SVGTransform object is created with the same values as newItem and this item is inserted into the list.
+    // Otherwise, newItem itself is inserted into the list.
+    if (newItem->ownerList())
+        return Base::appendItem(newItem->clone());
+
+    return Base::appendItem(newItem);
+}
+
+PassRefPtrWillBeRawPtr<SVGTransform> SVGTransformList::insertItemBefore(PassRefPtrWillBeRawPtr<SVGTransform> passNewItem, size_t index)
+{
+    RefPtrWillBeRawPtr<SVGTransform> newItem = passNewItem;
+
+    // SVG2-Draft Spec: If newItem is already in a list, then a new SVGTransform object is created with the same values as newItem and this item is inserted into the list.
+    // Otherwise, newItem itself is inserted into the list.
+    if (newItem->ownerList())
+        return Base::insertItemBefore(newItem->clone(), index);
+
+    return Base::insertItemBefore(newItem, index);
+}
+
+PassRefPtrWillBeRawPtr<SVGTransform> SVGTransformList::replaceItem(PassRefPtrWillBeRawPtr<SVGTransform> passNewItem, size_t index, ExceptionState& exceptionState)
+{
+    RefPtrWillBeRawPtr<SVGTransform> newItem = passNewItem;
+
+    // SVG2-Draft Spec: If newItem is already in a list, then a new SVGTransform object is created with the same values as newItem and this item is inserted into the list.
+    // Otherwise, newItem itself is inserted into the list.
+    if (newItem->ownerList())
+        return Base::replaceItem(newItem->clone(), index, exceptionState);
+
+    return Base::replaceItem(newItem, index, exceptionState);
+}
+
 }