Merged revisions 82413,82468 via svnmerge from

Merged revisions 82413,82468 via svnmerge from
svn+ssh://pythondev@svn.python.org/python/branches/py3k

........
  r82413 | ezio.melotti | 2010-07-01 10:32:02 +0300 (Thu, 01 Jul 2010) | 13 lines

  Update PyUnicode_DecodeUTF8 from RFC 2279 to RFC 3629.

  1) #8271: when a byte sequence is invalid, only the start byte and all the
     valid continuation bytes are now replaced by U+FFFD, instead of replacing
     the number of bytes specified by the start byte.
     See http://www.unicode.org/versions/Unicode5.2.0/ch03.pdf (pages 94-95);
  2) 5- and 6-bytes-long UTF-8 sequences are now considered invalid (no changes
     in behavior);
  3) Change the error messages "unexpected code byte" to "invalid start byte"
     and "invalid data" to "invalid continuation byte";
  4) Add an extensive set of tests in test_unicode;
  5) Fix test_codeccallbacks because it was failing after this change.
........
  r82468 | ezio.melotti | 2010-07-03 07:52:19 +0300 (Sat, 03 Jul 2010) | 1 line

  Update comment about surrogates.
........