[graphite] Implement RuntimeEffect toLinearSrgb/fromLinearSrgb handling

In Graphite, for any RuntimeEffect that uses the intrinsics, we always upload the colorSpace uniforms and generate the colorSpace conversion code. If the dest ColorSpace is nullptr or is already LinearSRGB the color space conversion just becomes a noop.

Bug: b/40044496 (aka skia:13508)
Bug: b/331445583
Change-Id: I455b95ad3150a28ec92c9a9d236890f15782ba3d
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/833428
Commit-Queue: Robert Phillips <robertphillips@google.com>
Reviewed-by: John Stiles <johnstiles@google.com>
3 files changed