Impact of color space on color operations

[svgeesus]

Originally raised on the TAG review of Lab

@dbaron wrote:

the list of things whose behavior is changed by the color-interpolation property and the color-interpolation-filters property is a good list of things that do math on colors (more generally, I think it comes down to compositing, gradients, animations, and filters, most of which have CSS and SVG pieces that might be a little different)

[palemieux]

Suggest adding to the report a list of operations that are color-related.