[canvaskit] expose SkColorFilter and add SkColorMatrix helpers

of note, this is kjlubick's 2^9 = 512'th commit into the Skia repo.

Change-Id: I635cb1db6812217358ab138cd833c0c61f676232
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/241037
Reviewed-by: Mike Reed <reed@google.com>
6 files changed