Have NodeTraversal::nextSkippingChildren() take a reference

Source/core/dom/NodeTraversal.cpp

Index: Source/core/dom/NodeTraversal.cpp
diff --git a/Source/core/dom/NodeTraversal.cpp b/Source/core/dom/NodeTraversal.cpp
index e07b695893546b0c567a5a79edb4bb4af5fc34df..1ec16961d852b29263ce18f6fb46e3d64359fc48 100644
--- a/Source/core/dom/NodeTraversal.cpp
+++ b/Source/core/dom/NodeTraversal.cpp
@@ -74,25 +74,25 @@ Node* nextIncludingPseudoSkippingChildren(const Node* current, const Node* stayW
     return 0;
 }
 
-Node* nextAncestorSibling(const Node* current)
+Node* nextAncestorSibling(const Node& current)
 {
-    ASSERT(!current->nextSibling());
-    for (current = current->parentNode(); current; current = current->parentNode()) {
-        if (current->nextSibling())
-            return current->nextSibling();
+    ASSERT(!current.nextSibling());
+    for (Node* parent = current.parentNode(); parent; parent = parent->parentNode()) {
+        if (parent->nextSibling())
+            return parent->nextSibling();
     }
     return 0;
 }
 
-Node* nextAncestorSibling(const Node* current, const Node* stayWithin)
+Node* nextAncestorSibling(const Node& current, const Node* stayWithin)
 {
-    ASSERT(!current->nextSibling());
+    ASSERT(!current.nextSibling());
     ASSERT(current != stayWithin);
-    for (current = current->parentNode(); current; current = current->parentNode()) {
-        if (current == stayWithin)
+    for (Node* parent = current.parentNode(); parent; parent = parent->parentNode()) {
+        if (parent == stayWithin)
             return 0;
-        if (current->nextSibling())
-            return current->nextSibling();
+        if (parent->nextSibling())
+            return parent->nextSibling();
     }
     return 0;
 }