Add use of RG textures in wacky_yuv_formats

Bug: skia:7903
Change-Id: I77346b301777479694b051486d95d720d8fd179f
Reviewed-on: https://skia-review.googlesource.com/c/175360
Reviewed-by: Brian Salomon <bsalomon@google.com>
Commit-Queue: Jim Van Verth <jvanverth@google.com>
2 files changed