Fix compilation with MSVC2013 & C++11 support

See Variadic templates issue: https://connect.microsoft.com/VisualStudio/feedback/details/801828/c2143-error-when-compiling-c-code-with-variadic-templates

Task-number: QTBUG-34705

Change-Id: I733f1451f6d1e9b958c3a76998810fcff3fe779b
Reviewed-by: Yuchen Deng <loaden@gmail.com>
Reviewed-by: Marc Mutz <marc.mutz@kdab.com>
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
Reviewed-by: Olivier Goffart <ogoffart@woboq.com>

src/corelib/kernel/qobject_impl.h

@@ -99,6 +99,8 @@ namespace QtPrivate {
 
     template <typename ArgList, bool Declared = TypesAreDeclaredMetaType<ArgList>::Value > struct ConnectionTypes
     { static const int *types() { return 0; } };
+    template <> struct ConnectionTypes<List<>, true>
+    { static const int *types() { return 0; } };
     template <typename... Args> struct ConnectionTypes<List<Args...>, true>
     { static const int *types() { static const int t[sizeof...(Args) + 1] = { (QtPrivate::QMetaTypeIdHelper<Args>::qt_metatype_id())..., 0 }; return t; } };
 #endif