cc0ffa0766
* align the definition of the exception class with how ProcessException ended up * add constants for redability R=ager@google.com BUG= TEST= Review URL: https://chromereviews.googleplex.com/3551012 git-svn-id: https://dart.googlecode.com/svn/branches/bleeding_edge/dart@98 260f80e4-7a28-3924-810f-c04153c831b5