Reland "Snap coordinates for shader nearest-neighbor decal filtering"

This is a reland of 4e68ec693fdbb1a074b744f78e4999b60b517389

Original change's description:
> Snap coordinates for shader nearest-neighbor decal filtering
> 
> Bug: skia:10403
> Change-Id: I875b1a4bb7cacbe6721a69aa8ed02118b989729d
> Reviewed-on: https://skia-review.googlesource.com/c/skia/+/297596
> Reviewed-by: Brian Salomon <bsalomon@google.com>
> Commit-Queue: Michael Ludwig <michaelludwig@google.com>

Bug: skia:10403
Change-Id: Idcf0b9a2d85410901a6d6fc2bedf628122cf9ae4
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/297799
Reviewed-by: Michael Ludwig <michaelludwig@google.com>
Reviewed-by: Brian Salomon <bsalomon@google.com>
Commit-Queue: Michael Ludwig <michaelludwig@google.com>
1 file changed