code: func (s *CombinedPrimitiveSlice) UpsertRecorded(l interface{}) {
  	v := s.upsert(l)
  	v.recorded = l
  	v.recordedSet = true
  }
docs: // UpsertRecorded adds l to the slice.  If there is already a value of l in the
  // slice for either the local or remote, set on that value as the recorded value
  // Otherwise append a new item to the list with the recorded value.