Directly compute normalized coords in the color cube runtime effect

We can compute these directly, and avoid a whole extra matrix uniform
and multiply to get the same effect.

Change-Id: I25146932fd577f64567abee8df2c001a830ef78f
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/292574
Reviewed-by: Brian Salomon <bsalomon@google.com>
Commit-Queue: Brian Osman <brianosman@google.com>
1 file changed