NOTE: The _PR_InvalidInt16 is part of _pr_faulty_methods where it is a dummy for the poll function (PRPollFN)_PR_InvalidInt16 and _pr_faulty_methods seem to only be in use when NSPR FD caching is enabled and it is used when an fd is put back onto cache. The FD caching is supposed to be enabled ONLY on DEBUG NSPR builds.