Cyrax = happened

Mileena = didn't happen
Kitana's not dead and when we next see Mileena, she's in the Edenian prison.

Kitana = maybe happened. Perhaps Mileena fell into the prison that she was being held in in MKD instead of dying?

Kung Lao = happened

Baraka = didn't happen
Baraka's not dead and Quan-Chi didn't take over in the end.

Sonya = maybe happened. So far, nothing's contradicted it.

Jax = didn't happen.
Sonya didn't die.

Liu Kang = happened

Johnny Cage = happened

SubZero = didn't happen
Quan-Chi didn't die.

Reiko = Clueless. One of Konquest's side quests says that Reiko joined Shao Kahn's army against Edenia after Shinnok was defeated, but the side quests aren't canon. So, uh.....I dunno. This ending was always mysterious.

Jarek =didn't happen
Sonya didn't die.

Raiden =happened

Tanya =didn't happen
The good guys won and Liu Kang didn't die.

Scorpion =happened.

Kai =didn't happen.
Raiden still has his lightning stuff, and don't try to tell me about the mission in Konquest involving the staff, because any side quest not involved in the actual story is not canon.

Reptile =didn't happen
Reptile didn't die, and the good guys won.

Shinnok =didn't happen
Raiden's still alive, and the good guys won, meaning Shinnok got his ass beat.

Fujin =happened (although we have not seen Fujin since MK4, not counting the side quest in Konquest, a member of the MK team has confirmed that Fujin was made the protector of Earthrealm when Raiden was made an Elder God).

Quan-Chi =didn't happen
Quan-Chi may have had the real amulet all along (that part is true), but he did not kill Shinnok. Liu Kang did (confirmed in Konquest / Deception). Plus, in the end, Quan-Chi ends up in the Netherealm.

Sektor = didn't happen
Jax, Sonya, and Cyrax are still alive.