typing: fix argument type of encoding.localstr() It takes both utf-8 and local strings in bytes type.

typing: suppress error of py2 encoding.strtolocal() and .strfromlocal() I don't know how to conditionally get rid of these py2/py3 overloads from .pyi file. Instead, this patch makes pytype ignore the false-positives: line 271, in strtolocal: bad option in return type [bad-return-type] Expected: bytes Actually returned: str

typing: constrain argument/return types of encoding.toutf8b()