Do not special case null for URLUtils attributes

LayoutTests/fast/dom/HTMLAnchorElement/script-tests/set-href-attribute-hash.js

Index: LayoutTests/fast/dom/HTMLAnchorElement/script-tests/set-href-attribute-hash.js
diff --git a/LayoutTests/fast/dom/HTMLAnchorElement/script-tests/set-href-attribute-hash.js b/LayoutTests/fast/dom/HTMLAnchorElement/script-tests/set-href-attribute-hash.js
index 3005a01bfcae946da1cb4aa348953e5e9215b3d0..66d6c9719906b0ff3cb07d606b507931a85f837c 100644
--- a/LayoutTests/fast/dom/HTMLAnchorElement/script-tests/set-href-attribute-hash.js
+++ b/LayoutTests/fast/dom/HTMLAnchorElement/script-tests/set-href-attribute-hash.js
@@ -24,13 +24,10 @@ a.href = "https://www.my\"d(){}|~om?ain#com/path/testurl.html#middle";
 a.hash = "#hash#value";
 shouldBe("a.href", "'https://www.my\"d(){}|~om?ain#com/path/testurl.html#middle'");
 
-// IE8 converts null to "null", which is not the right thing to do.
-// Firefox 3.5.2 removes the '#' at the end, and it should per
-// http://dev.w3.org/html5/spec/infrastructure.html#url-decomposition-idl-attributes .
 debug("Set hash to null");
 a.href = "https://www.mydomain.com/path/testurl.html#middle";
 a.hash = null;
-shouldBe("a.href", "'https://www.mydomain.com/path/testurl.html#'");
+shouldBe("a.href", "'https://www.mydomain.com/path/testurl.html#null'");
 
 // Firefox 3.5.2 removes the '#' at the end, and it should per
 // http://dev.w3.org/html5/spec/infrastructure.html#url-decomposition-idl-attributes .