About halfway through Batman vs Superman, Bruce Wayne falls asleep and has couple of rather unusual dreams. In one of them, a person appears to be trying to give him a message.
He appears to be coming out of a portal and surrounded by lightning, and is trying to tell Bruce about Lois Lane and Superman.
The whole scene is incredibly confusing, since the message is definitely something Bruce wouldn't know enough to dream about, and it's never brought up again. Multiple people have complained about this "confusing Flash cameo".
When I saw it, it never occurred to me that it was supposed to be the Flash, because
He seemed to be wearing a mechanical suit, and had no control over his use of the portal; not to mention, the message made no sense.
Was the actor in this scene Ezra Miller -- the same one who later appears in a definitive Flash cameo -- and was this supposed to be a message from the Flash?
UPDATE:
Please note: I am not asking what the message meant, or how The Flash might be the one sending it, or what the comics have to say, because I know the answers to all of those things. I'm only asking if the character in this scene is shown to be the same character we see in the security footage from the convenience store in a later scene.