Revert r81171 (posix_listdir(), posix_readlink(): avoid temporary PyBytes object)
Revert r81171 (posix_listdir(), posix_readlink(): avoid temporary PyBytes object)

PyUnicode_DecodeFSDefault*() doesn't use surrogateescape error handler, and so
PyUnicode_FromEncodedObject(v, Py_FileSystemDefaultEncoding, "surrogateescape")
cannot be replaced by PyUnicode_DecodeFSDefault().

It's a bad idea to try to fix surrogates things in Python 3.1...

sk-/python2.7-type-annotator,sk-/python2.7-type-annotator,sk-/python2.7-type-annotator