eolian-cxx: Handle exclicitly void-return getters.

Whenever a getter explicitly defines a void return the generated code
shall not convert single-parameter getters in any ways.

Actually the correct approach would be to delegate all conversions to
Eolian Database instead of for the generators.

src/bin/eolian_cxx/convert.cc

@@ -101,7 +101,8 @@ convert_eolian_property_to_functions(Eolian_Class const& klass)
              // if the getter has a single parameter and a void return
              // it is transformed into a getter with no parameters
              // that actually returns what would be the first argument.
-             if (params.size() == 1 && efl::eolian::type_is_void(ret))
+             if (params.size() == 1 && efl::eolian::type_is_void(ret) &&
+                 !function_return_is_explicit_void(*prop_, eolian_cxx::getter))
                {
                   get_.ret = params[0].type;
                   get_.params.clear();

src/bin/eolian_cxx/eolian_wrappers.hh

@@ -207,6 +207,16 @@ function_return_type(Eolian_Function const& func, ctor_t func_type)
    return function_return_type(func, func_type.value);
 }
 
+inline bool
+function_return_is_explicit_void(Eolian_Function const& func, getter_t func_type)
+{
+   // XXX This function shouldn't be necessary. Eolian database should
+   //     forge functions as desired and the bindings generator shouldn't
+   //     be required to convert and understand this.
+   Eolian_Type const* type = ::eolian_function_return_type_get(&func, func_type.value);
+   return !!type && safe_str(type->name) == "void";
+}
+
 inline bool
 property_is_getter(Eolian_Function_Type func_type)
 {