Participants counted even when marked as "0" on price set line item

[This issue was originally reported in Jira as CRM-20784. Bringing it here to make sure it doesn't get lost as it continues to be a bug in 5.13.5]

When creating a price set, you can set the number of participants who should be counted for that price option. In this use case, I was setting up a price option for a table (with a participant count of 8) and for a table guest (with a participant count of 0). This way, the person purchasing the table could choose whether or not to register the actual names and emails of the additional table guests without paying more or having them count toward the total number. When testing, the table price option worked as expected, counting 8 participants, but the table guest still counted as 1. If there's an option to set the participant count to 0, then it should not calculate accordingly in the Actual Participant Count.