When working with speed strips, it is very annoying not to know when hold/freeze frames will be created. This patch adds hold drawing on speed strips in Frame Number and Length modes. To avoid confusion between f-curve drawing, which is dark, and the hold areas, the latter are changed to light(including out of frame range holds).

Some of the code doubles with this speed strip f-curve drawing patch: D6110

Maybe Multiply can be added too - that would need to check if target frame is having a flat curve(by ex. running out of frames).