Make createAttributeNS's qualifiedName argument non-nullable

LayoutTests/fast/dom/Document/script-tests/createAttributeNS-namespace-err.js

 description("createAttirbuteNS tests adapted from createElementNS tests attached to webkit bug 16833");
 
 function assert(c, m)
 {
     if (!c)
         testFailed(m);
     else
         testPassed(m);
 }
 
@@ skipping 20 matching lines @@
         testFailed(m);
     } else {
         m += "; threw " + exception.toString();
         testPassed(m);
     }
 }
 
 var allNSTests = [
    { args: [undefined, undefined] },
    { args: [null, undefined] },
-   { args: [undefined, null], code: 5 },
-   { args: [null, null], code: 5 },
+   { args: [undefined, null] },
+   { args: [null, null] },
    { args: [null, ""], code: 5 },
-   { args: ["", null], code: 5 },
+   { args: ["", null] },
    { args: ["", ""], code: 5 },
    { args: [null, "<div>"], code: 5 },
    { args: [null, "0div"], code: 5 },
    { args: [null, "di v"], code: 5 },
    { args: [null, "di<v"], code: 5 },
    { args: [null, "-div"], code: 5 },
    { args: [null, ".div"], code: 5 },
    { args: ["http://example.com/", "<div>"], code: 5 },
    { args: ["http://example.com/", "0div"], code: 5 },
    { args: ["http://example.com/", "di<v"], code: 5 },
@@ skipping 63 matching lines @@
         try {
             createFunction.apply(doc, test.args);
             assert(!("code" in test), msg);
         } catch (e) {
             assertExceptionCode(e, test.code || "expected no exception", msg);
         }
     }
 }
 
 runNSTests();