So hear is the deal with the whole funeral thing.
I dont think it is Cam's funeral. Its been to long since his death, funerals would usually happen closer to the death of the person, not after a whole summer. Also, his funeral probably wouldn't have been in Toronto but probably back home where his family would probably want it.
I also don't think its Adam's funeral either. First, they killed off a main character last season and I doubt they would have another death so close to it. Also, considering the direction Adam's character has gone, I think it would be the completely wrong way for him to leave the show, and I think the writers realize that.
If it is a funeral (some people are suggesting it is the mv promo) I think that it most likely not a main character and maybe a parent or some one else.