Fixed Can't create two event listeners for the same event and callback

[refael]

Affected version

2.0.0 beta 5

It seems it's impossible to create more than one listener for the same event and callback.
I'm trying to add multiple listeners with a different hint. This was possible in xf1.

I'm getting a database error complaining about duplicated entry for the unique key: addon_id_event_id_class_method

 

[Kier]

We've now dropped the index, so you'll be able to add multiple listeners with the same callback, as before.