We need a way to harmonize autobins across traces, and that it needs to know about cumulative. To make this example work I needed to manually extend the bin range for the red trace, otherwise its CDF ended too soon. Actually, CDFs never end, really... so perhaps the even better thing to do would be to look at the axis range and draw bins out to the edge, while still only using the real data for autoranging? We also need to make sure bin sizes and edges match, which is needed for non-cumulative histograms as well.

Originally mentioned in #1189 (comment)