Callbacks with memory are unlocked by add

Moved from https://github.com/jquery/api.jquery.com/issues/1013#issuecomment-268428574

### Description ###
`add` erroneously unlocks Callbacks with memory.

### Link to test case ###
https://jsfiddle.net/o0f244cc/