[graphite] Add ColorFilterShader support

Change-Id: If0838077230fd4e69f249d2d90bf4bf11b9782a1
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/597019
Commit-Queue: Robert Phillips <robertphillips@google.com>
Reviewed-by: John Stiles <johnstiles@google.com>
7 files changed