Fix SkSampler::Fill/Gray_8 when width != stride

Bug: skia:
Change-Id: I68296bc9902c008d30a0ef1e748f22edd8c56255
Reviewed-on: https://skia-review.googlesource.com/150780
Reviewed-by: Leon Scroggins <scroggo@google.com>
Commit-Queue: Leon Scroggins <scroggo@google.com>
1 file changed