autodiscount not working if multiple discount instances for same event type

Created by: MtnPavlas

Only the first instance of an auto-discount for a specific event type works while any subsequent instances don't. E.g. let's assume two discount instances being set up for event type "Class" - one for $20 off, another one for $35 off - each of them has different price options assigned and the same membership requirements to drive the auto-discount, but the $35 auto-discount doesn't work. Entering the discount code on the event registration page manually works just fine, but the auto-discount doesn't (logged in user is a current member). No errors in the logs or console.

This worked on CiviDiscount v3.2 and hasn't worked since 3.4 (we skipped 3.3 so can't speak for that version). I just verified 3.2 worked by re-installing it on our website. Submitting this bug after chatting with Eileen on Town Square.