Long black market game results in visual bugs

[dan]

Issues in: #628947 on oregon

There were some stability issues at the end of a long black market game.

After attempting to undo a princed cellar, the client begins to slow down for all three players in the game. After a (maybe related) blue screen, logging in takes longer than usual as well.

On turn 20, I attempt to undo an action phase crown, which results in a number of visual bugs. Buying black market appeared to reduce the black market in supply by two. Each card in my hand had a two in the upper left.

Really weird. Early game was fine. I think undo was related.