Default argument is not used for more complex types

If there is a function with default argument, it doesn't seem to be used if it is a bit more complex type. For example std::pair argument doesn't take the default argument in generated wrapper.

To reproduce run attached example. It prints "got pair 0,0" for a call to set_pair(std::pair<int,int> = std::pair(123,123));. In icecream_wrapper.cpp it can be seen to not pass the default argument to cppArg0:

        ::std::pair<int,int> cppArg0;
        if (pythonToCpp[0])
            pythonToCpp[0](pyArgs[0], &cppArg0);

        if (!Shiboken::Errors::occurred()) {
            // set_pair(std::pair<int,int>)
            cppSelf->set_pair(cppArg0);
        }

but it works if the argument type is int.