Have getElementsByClassName() / getElementsByTagName*() return an HTMLCollection

LayoutTests/fast/dom/wrapper-classes.html

Index: LayoutTests/fast/dom/wrapper-classes.html
diff --git a/LayoutTests/fast/dom/wrapper-classes.html b/LayoutTests/fast/dom/wrapper-classes.html
index d9841be1da6de9830655d26e3a458f124ca928bb..8d094f48cee076467adf32134bd040e010b063a7 100644
--- a/LayoutTests/fast/dom/wrapper-classes.html
+++ b/LayoutTests/fast/dom/wrapper-classes.html
@@ -84,7 +84,7 @@ function runTest()
     test("document.implementation", "DOMImplementation");
     test("root.attributes", "NamedNodeMap");
     test("document.createNodeIterator(root, 0, null, false)", "NodeIterator");
-    test("document.getElementsByTagName('div')", "NodeList");
+    test("document.getElementsByTagName('div')", "HTMLCollection");
     test("document.createRange()", "Range");
     test("document.createTextNode('')", "Text");
     test("document.createTreeWalker(root, 0, null, false)", "TreeWalker");