Added an optimization to tell the scatterplot that points with undefined nominate actually don't exist, rather than just plotting them outside the canvas.
Added an optimization to tell the scatterplot that points with undefined nominate actually don't exist, rather than just plotting them outside the canvas.


Former-commit-id: de7a0674ae0f5e90227ff6f430f7fe4653f5adb1
JeffreyBLewis/WebVoteView,JeffreyBLewis/WebVoteView,JeffreyBLewis/WebVoteView,JeffreyBLewis/WebVoteView