unanimously agreed to rollback the deletion API.  We all support the
  features this patch added, yet not its actual design and implementation.
  After some talk, we decided that it would be better for Drupal -- in the
  long term -- not to go with a solution that isn't 100%. We also recognize
  that in the short term, this patch would have been useful addition. So
  let's figure out how we can implement this properly in D7.