John Constantine: I did tell you to move the car.
Chaz: Yeah, well if you'd have told me that there was going to be a 300 pound mirror with a pissed off demon inside it falling from a window, I would've moved it further, John.
When Constantine manage to get the mirror through the window he falls on his back. To the right on the screen a chair lies on the floor beside a dresser. A few shots later when it cuts to Constantine getting up we can see the chair has changed position as its back now covers the opening of the dresser.
Stay after the credits. There's an additional scene where John goes to visit Chas' grave and leaves a lighter, then as he's walking away you see Chas with wings and he flies up into the sky.