[docs] [issue11726] clarify that linecache only works on files that can be decoded successfully

[Roundup Robot]

Roundup Robot added the comment:

New changeset 01cb2107cbc3 by Victor Stinner in branch '3.4':
Issue #11726: Fix linecache example in the doc
https://hg.python.org/cpython/rev/01cb2107cbc3

----------

_______________________________________
Python tracker <report at bugs.python.org>
<http://bugs.python.org/issue11726>
_______________________________________