Merged revisions 73871 via svnmerge from

Merged revisions 73871 via svnmerge from
svn+ssh://pythondev@svn.python.org/python/trunk

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  r73871 | alexandre.vassalotti | 2009-07-06 22:17:30 -0400 (Mon, 06 Jul 2009) | 7 lines

  Grow the allocated buffer in PyUnicode_EncodeUTF7 to avoid buffer overrun.

  Without this change, test_unicode.UnicodeTest.test_codecs_utf7 crashes in
  debug mode. What happens is the unicode string u'\U000abcde' with a length
  of 1 encodes to the string '+2m/c3g-' of length 8. Since only 5 bytes is
  reserved in the buffer, a buffer overrun occurs.
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