Runtime shaders, color filters, and blenders are all able to sample from
a blender. These use the blend-function signature; both a src-color and
dst-color must be passed to sample. i.e.: sample(blender, s, d)
Change-Id: I3738e6b0b4af6d1d79e62ca1815c80d6a1ae9d6f
Bug: skia:12257
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/432056
Commit-Queue: John Stiles <johnstiles@google.com>
Reviewed-by: Brian Osman <brianosman@google.com>
ce9a5c953d