Blender Git Loki

Fix: Grease Pencil strokes rendered with blotched colours/alpha in OpenGL Playblasts

Thanks to an anonymous tip (or shall we say, a tip from "Anonymous" - thank you
whoever you are :) it is now possible to render out Grease Pencil shots from
the viewport with correct colours again! This has been broken for a few releases
now, so it's great that this works again now, completing the last part of the
pipeline again.