Fixes bug 6380625 which was another case when we had two stub frames before hitting the dart frame. Review URL: https://chromiumcodereview.appspot.com//10173008 git-svn-id: https://dart.googlecode.com/svn/branches/bleeding_edge/dart@6920 260f80e4-7a28-3924-810f-c04153c831b5
git-svn-id: https://dart.googlecode.com/svn/branches/bleeding_edge/dart@15 260f80e4-7a28-3924-810f-c04153c831b5