HSL sliders jumping. The issue here is that we store HSV in display space.
To correctly account for that, made sure HSV/HSL is now using the displayed
color to compute the values in the sliders. RGB values still show
the property values (linear for linear, gamma corrected for gamma corrected)
We could change the way we store HSV, but we would need to add many more
conversions in the picker code to account for storing it that way.
My fix takes into account the way HSV is stored in HSVCube as well in the code.
Color pickers should help with visible color selection, but since having
HSV be in property display space has been a design choice this will go
through review.