Guess that shouldn't be needed anymore. Before Piwik 2.15 we used to have another array format for defining search engines. So if anyone would still use this old format with the event
Referrer.addSearchEngineUrls, that might not work anymore. But as that event is not even marked as API, I guess that should be fine.
btw all Events are marked as API unless we specifically say to ignore it. That's why it appears here: https://developer.matomo.org/api-reference/events#referreraddsearchengineurls
should still be fine to merge though.