since %DebugPrint is not often used.  Needed for some performance testing
statistics outputting.

Fix the declaration of descriptor enumerated constants to be more readable.
Review URL: http://codereview.chromium.org/3100

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@332 ce2b1a6d-e550-0410-aec6-3dcde31c8c00