Blender Git Loki

Fix T37670: Paint mode + procedural map colours error

Summary:
Seems to be known TODO in the code, but no idea why it
was never solved, especially since tweak is so much easy.

It might be arguable that we need to support painting
color space, but it's still much better to convert to
sRGB space. It's gonna to cover 90% of cases anyway.

Reviewers: campbellbarton, brecht

Reviewed By: brecht

Maniphest Tasks: T37670

Differential Revision: https://developer.blender.org/D65