aa8f2cf676
Added more infrastructure to detect errors in the patch. Still no ability to add an element from the patch to the original library. Review URL: https://chromiumcodereview.appspot.com//10697084 git-svn-id: https://dart.googlecode.com/svn/branches/bleeding_edge/dart@9457 260f80e4-7a28-3924-810f-c04153c831b5