Extend "ignore" parameter test

- Ensure that `argout` is called even when a parameter is ignored
- Ensure that ignored parameters with default arguments are handled
  correctly

Examples/test-suite/ignore_parameter.i

@@ -3,14 +3,19 @@
 %module ignore_parameter
 
 %typemap(in,numinputs=0) char* a "static const char* hi = \"hello\"; $1 = const_cast<char *>(hi);";
-%typemap(in,numinputs=0) int bb "$1 = 101;";
+%typemap(in,numinputs=0) int bb "$1 = 101; called_argout = 0;";
 %typemap(in,numinputs=0) double ccc "$1 = 8.8;";
 
 %typemap(freearg) char* a ""; // ensure freearg is not generated (needed for Java at least)
 
+%typemap(argout) int bb "called_argout = 1;"
+
 %ignore unignorable;
 
 %inline %{
+// constant for detecting correct "argout" call
+int called_argout = 0;
+
 // global function tests
 char* jaguar(char* a, int b, double c) { return a; }
 int lotus(char* aa, int bb, double cc) { return bb; }
@@ -25,6 +30,7 @@ struct SportsCars {
   double bugatti(char* aaa, int bbb, double ccc) { return ccc; }
   int lamborghini(int bb) { return bb; }
   int maseratti(int unignorable) { return unignorable; }
+  double audi(double ccc=9.5) { return ccc; }
 };
 
 // constructor tests