Use new Traversal<HTML*Element> API in HTML code

Source/core/html/HTMLMapElement.cpp

Index: Source/core/html/HTMLMapElement.cpp
diff --git a/Source/core/html/HTMLMapElement.cpp b/Source/core/html/HTMLMapElement.cpp
index 00f7032c8087ddc0773a7a9d044e7bbb7bae11fa..02c70e977a7fe086c09bb0e45555cba40f0364e2 100644
--- a/Source/core/html/HTMLMapElement.cpp
+++ b/Source/core/html/HTMLMapElement.cpp
@@ -54,15 +54,12 @@ HTMLMapElement::~HTMLMapElement()
 bool HTMLMapElement::mapMouseEvent(LayoutPoint location, const LayoutSize& size, HitTestResult& result)
 {
     HTMLAreaElement* defaultArea = 0;
-    Element* element = this;
-    while ((element = ElementTraversal::next(*element, this))) {
-        if (element->hasTagName(areaTag)) {
-            HTMLAreaElement* areaElt = toHTMLAreaElement(element);
-            if (areaElt->isDefault()) {
-                if (!defaultArea)
-                    defaultArea = areaElt;
-            } else if (areaElt->mapMouseEvent(location, size, result))
-                return true;
+    for (HTMLAreaElement* area = Traversal<HTMLAreaElement>::firstWithin(*this); area; area = Traversal<HTMLAreaElement>::next(*area, this)) {
+        if (area->isDefault()) {
+            if (!defaultArea)
+                defaultArea = area;
+        } else if (area->mapMouseEvent(location, size, result)) {
+            return true;
         }
     }