"Accidentally" fixed a bug with overloading of functions with

Objective-C objects as parameters in r146659. Add a test for it.

llvm-svn: 146660

clang/test/SemaObjCXX/overload.mm

@@ -171,3 +171,9 @@ namespace rdar9327203 {
     int &fr = (f)(x, 0); 
   }
 }
+
+namespace class_id {
+  // it's okay to overload Class with id.
+  void f(Class) { }
+  void f(id) { }
+}