expand protected using testcase

git-svn-id: https://swig.svn.sourceforge.net/svnroot/swig/trunk@12404 626c5289-ae23-0410-ae9c-e8d60b6d4f22

Examples/test-suite/using_protected.i

@@ -5,12 +5,21 @@ class Foo {
 protected:
   int x;
   int blah(int xx) { return xx; }
+  virtual int vmethod(int xx) { return xx; }
 };
 
 class FooBar : public Foo {
 public:
   using Foo::blah;
   using Foo::x;
+  using Foo::vmethod;
+};
+
+class FooBaz : public Foo {
+protected:
+  using Foo::blah;
+  using Foo::x;
+  using Foo::vmethod;
 };
 
 %}