t3901: test git-am encoding conversion
t3901: test git-am encoding conversion

Since d1c5f2a (Add git-am, applymbox replacement., 2005-10-07), git-am
supported the --utf8 and --no-utf8 options, and if set, would pass the
-u flag and the -k flag respectively.

git mailinfo -u will re-code the commit log message and authorship info
in the charset specified by i18n.commitencoding setting, while
git mailinfo -n will disable the re-coding.

Since d84029b (--utf8 is now default for 'git-am', 2007-01-08), --utf8
is set by default in git-am.

Add various encoding conversion tests to t3901 to test git-mailinfo's
encoding conversion. In addition, add a test for --no-utf8 to check that
no encoding conversion will occur if that option is set.

Helped-by: Johannes Sixt <fd432345609ae4d58c1aa629cb66ba96d1391622@kdbg.org>
Reviewed-by: Stefan Beller <a7f3b1612c245dae606b3b9617b4f52187fddb65@google.com>
Reviewed-by: Johannes Schindelin <53fb8db7833fca1e1746dd8592f61048d350f64c@gmx.de>
Signed-off-by: Paul Tan <ca5433e1cdd25b4a4001c54525dea593b33edc0c@gmail.com>
Signed-off-by: Junio C Hamano <a6723cc3f76163bf7adb636a73ac3b0ceb3e6b9b@pobox.com>

destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git