I apologize for the incorrect report regarding Roman Reigns defeating Brock Lesnar for the Heavyweight Title at WrestleMania. Here is the correct report:
Right now, there is a lot of talk within the company that Brock Lesnar will defeat John Cena for the Heavyweight Championship then for him to build for a match at WrestleMania 31 against Roman Reigns. However, there is no confirmation from the company that Lesnar will be winning the title.
Sorry for the confusion.
Credit Dave Meltzer, Wrestling Observer Newsletter