Reason for revert:
Erg - dumb bug
Original issue's description:
> Create blurred RRect mask on GPU (rather than uploading it)
>
> This CL doesn't try to resolve any of the larger issues. It just moves the computation of the blurred RRect to the gpu and sets up to start using vertex attributes for a nine patch draw (i.e., returning the texture coordinates)
>
> All blurred rrects using the "analytic" path will change slightly with this CL.
>
> GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2222083004
>
> Committed: https://skia.googlesource.com/skia/+/75ccdc77a70ec2083141bf9ba98eb2f01ece2479TBR=bsalomon@google.com
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
Review-Url: https://codereview.chromium.org/2236493002
69cfa9c28d