#11554: reactivate test_email_codecs, and make it pass.

The fix is to charset.py, which was not doing the encoding to the
correct output character set when doing a body_encode for either
the shift-jis or euc-jp charsets.  There's also a fix for handling
a bytes input in encoders.py.

Patch by Michael Henry, comment changes by me.
diff --git a/Misc/NEWS b/Misc/NEWS
index a201895..adc719b 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -34,6 +34,9 @@
 Library
 -------
 
+- Issue #11554: Fixed support for Japanese codecs; previously the body output
+  encoding was not done if euc-jp or shift-jis was specified as the charset.
+
 - Issue #11500: Fixed a bug in the os x proxy bypass code for fully qualified 
   IP addresses in the proxy exception list. 
 
@@ -99,6 +102,8 @@
 Tests
 -----
 
+- Issue #11554: Reactivated test_email_codecs.
+
 - Issue #11490: test_subprocess:test_leaking_fds_on_error no longer gives a
   false positive if the last directory in the path is inaccessible.