He didn't see who it was she left (otherwise he would be laughing up a storm,) but that's a pretty telling exit, especially with the outfit. That's an 'I can't do this' exit, and it doesn't take a genius to figure out what, exactly, it is she can't do.

"Smooth," comes Eames' voice as he approaches the bar — low, but he knows she can hear him — hands in his pockets and a light smirk playing over his face as he stops in front of her. It's a fairly good guess that smooth is the last thing she was.