A group of well-dressed art supporters flocked to the Museum of Fine Arts for its Trustees’ Dinner on Saturday night. Guests included Governor Deval Patrick, Yo-Yo Ma and his wife, Jill Horner, arts reporter Joyce Kulhawik, and art historians Meg and Joseph Koerner. The group got to listen to writer Adam Gopnik talk about his favorite painting, “The Daughters of Edward Darley Boit” by John Singer Sargent.