[core] Added a static function to pick up when a null string was being passed to real_exception() and to provide a non-null string in that instance.  Is used in bitwise_and(), bitwise_or() and bitwise_xor().  This should resolve Coverity CIDs 120, 121, and 122.
[core] Added a static function to pick up when a null string was being
passed to real_exception() and to provide a non-null string in that
instance.  Is used in bitwise_and(), bitwise_or() and bitwise_xor().  This
should resolve Coverity CIDs 120, 121, and 122.


git-svn-id: 6e74a02f85675cec270f5d931b0f6998666294a3@21984 d31e2699-5ff4-0310-a27c-f18f2fbe73fe

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