Fix bump3d use of sample()

Change-Id: I75d7a4bdbfb2a5d22b85bca0cae2975378b19a53
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/269365
Reviewed-by: Brian Osman <brianosman@google.com>
Commit-Queue: Brian Osman <brianosman@google.com>
1 file changed