Bug 728188 - Add missing test for bug 728188. r=needed-tests

--HG--
extra : rebase_source : d9614d10872a2ae7808565bf941258e3b2e98b89

js/src/jit-test/tests/ion/bug728188.js

@@ -0,0 +1,9 @@
+// |jit-test| error:TypeError
+
+delete String.prototype.indexOf;
+
+function enterFunc (funcName) {
+    funcName.indexOf();
+}
+enterFunc(new Array("foo"));
+enterFunc(new String("Foo"));