Safe to eat!!??

So last night I went out to eat for my birthday. The restaurant gave me a free brownie and ice cream for my birthday but I decided to take it home. I scrape the ice cream off and took the brownie but I did not refrigerate it. There was a little bit of ice cream left on it and it sat out all night? Is the brownie safe to eat or should I throw it out because the little drop of ice cream on it sat out all night?