Fix line numbers on Python shell.

* lisp/progmodes/python.el (python-shell--save-temp-file): Do not
append coding cookie.
(python-shell-send-string): Generalize for
python-shell-send-region.
(python--use-fake-loc): Delete var.
(python-shell-buffer-substring): Cleanup fake-loc logic.
(python-shell-send-region): Remove fake-loc logic, simplify.
* lisp/progmodes/sh-script.el: Don't set global indent-line-function

Fixes: debbugs:19433

(sh-set-shell): Don't change the global value of indent-line-function.