Fixed misleading test

It didn't look quite right and when I debugged it in jQuery sure enough
it took 2 parameters rather than 1 (both values passed on)

jquery/jquery-tests.ts

@@ -2327,7 +2327,7 @@ function test_EventIsCallable() {
 }
 
 $.when($.ajax("/my/page.json")).then((a,b,c) => a.asdf); // is type JQueryPromise<any>
-$.when("asdf", "jkl;").done(x => x.length, x=> x.length);
+$.when("asdf", "jkl;").done((x,y) => x.length + y.length, (x,y) => x.length + y.length);
 
 var f1 = $.when("fetch"); // Is type JQueryPromise<string>
 var f2: JQueryPromise<string[]> = f1.then(s => [s, s]);