Never in my wildest dreams would I have expected this collaboration, but there it is. Brian Eno, founding member of Roxy Music, purveyor of ambient “Music for Airports” experimental records, and producer of U2 and the Talking Heads, is teaming with Paul Simon. “Surprise” is the all-too-fitting title, due for a May 9 release. Bill Frissell and Herbie Hancock are among the guests. One song, “Father and Daughter,” appeared on the “Wild Thornberries” soundtrack. Simon will appear May 13 on Saturday Night Live.