Fix unwrapping of LUA lightuserdata type. Add test case.

Examples/test-suite/lua/Makefile.in

@@ -15,6 +15,7 @@ top_builddir = @top_builddir@
 CPP_TEST_CASES += \
 	lua_no_module_global \
 	lua_inherit_getitem  \
+	lua_lightuserdata  \
 
 
 C_TEST_CASES += \

Examples/test-suite/lua/lua_lightuserdata_runme.lua

@@ -0,0 +1,7 @@
+require("import") -- the import fn
+require("lua_lightuserdata") -- import lib
+
+local t = lua_lightuserdata
+local d = t.get_lightuserdata()
+local r = t.check_lighuserdata(d)
+assert(r)

Examples/test-suite/lua_lightuserdata.i

@@ -0,0 +1,16 @@
+%module lua_lightuserdata
+
+%native(get_lightuserdata) int get_lightuserdata(lua_State* L);
+%{
+int get_lightuserdata(lua_State* L)
+{
+  lua_pushlightuserdata(L, reinterpret_cast<void*>(0x123456));
+  return 1;
+}
+%}
+
+%inline %{
+bool check_lighuserdata(const void* d) {
+  return reinterpret_cast<void*>(0x123456) == d;
+}
+%}