Re-enable test for all but Rhino (partial #679, still fails on Rhino)
Fix #898: Check existence of prototype of target in bind polyfill
Merge pull request #912 from gzm0/test-delete-fail

Re-enable test for all but Rhino (partial #679, still fails on Rhino)
Merge pull request #914 from gzm0/fix-polyfill

Fix #898: Check existence of prototype of target in bind polyfill