custom mesh produces color in user defined color space and alpha type

Bug: skia:12720
Change-Id: Icece250cd2642e63f9e04f139dc951f34f82c2ad
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/487383
Reviewed-by: Brian Osman <brianosman@google.com>
Commit-Queue: Brian Salomon <bsalomon@google.com>
6 files changed