This is one tolerant cat.  Either that or this cat has already gotten use to being around dogs.  The owners of these two are very lucky.  I remember when I brought my dog home for the first time.  We had four cats at the time, and we didn’t see any of them for about a month, lol.  Although after that they all got along just fine.  In fact one of the four cats became best friends with my dog and remained besties.