Merged revisions 80753 via svnmerge from

Merged revisions 80753 via svnmerge from
svn+ssh://pythondev@svn.python.org/python/trunk

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  r80753 | mark.dickinson | 2010-05-04 15:25:50 +0100 (Tue, 04 May 2010) | 10 lines

  Issue #8567: Fix incorrect precedence of signals in Decimal module.

  When a Decimal operation raises multiple signals and more than one of
  those signals is trapped, the specification determines the order in
  which the signals should be handled.  In many cases this order wasn't
  being followed, leading to the wrong Python exception being raised.
  This commit fixes those cases, and adds extra tests.  The tests are
  only enabled when EXTENDEDERRORTESTS is True, since they involve
  rerunning each Decimal testcase several times.
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