[css-filter-effects-1] color-interpolation-filters should respect the initial value

[svgeesus]

From 10. The color-interpolation-filters property

Initial: linearRGB

linearRGB Indicates that filter effects color operations should occur in the linear-light sRGB color space.

Originally reported by @hansottowirtz

The SVG filter operations should be done in sRGB space and not in display space (as is currently the case in Chromium, but not in Safari and Firefox))

Some implementations perform filter effects in whatever the display colorspace is, instead of in (linear-light) sRGB, thus giving completely wrong colors which are very visible.

• Proposed WPT test, using feColorMatrix
• Chromium bug
• Skia bug

[hansottowirtz]

I updated the wording to be more clear (Chromium has the bug):

The SVG filter operations should be done in sRGB space and not in display space (Safari and Firefox use sRGB space, Chromium uses display space)