Merge "init: log failures if a service cannot start during class_start"

static Result<Success> do_class_start(const BuiltinArguments& args) {

    // Starting a class does not start services which are explicitly disabled.

    // They must  be started individually.

    ForEachServiceInClass(args[1], &Service::StartIfNotDisabled);

    for (const auto& service : ServiceList::GetInstance()) {

        if (service->classnames().count(args[1])) {

            if (auto result = service->StartIfNotDisabled(); !result) {

                LOG(ERROR) << "Could not start service '" << service->name()

                           << "' as part of class '" << args[1] << "': " << result.error();

            }

        }

    }

    return Success();

}