Via Comics Alliance comes a leaked, alternate opening to Iron Man 2. At least one of the trailers for the film used a line from this scene, meaning the filmmakers were definitely planning on using it at some point, then changed their minds.
I can't remember how the theatrical cut actually opened—I think it was with a montage of Mickey Rourke grumbling at his pet bird and glaring at newspaper clippings of Tony Stark while he made his lightsaber whip things?—but I will say this: the version in theaters definitely did not open with a shot of Robert Downey Jr.'s head submerged in a toilet. Which is too bad, 'cause I totally would've bought that action figure.