Reduce needless spread of GrNonAtomicRef.h

Just noticed in passing that this was being used more broadly than warranted

Change-Id: I233060a272c4ed6b7fde7b830cbb5b16cad4cb29
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/319350
Reviewed-by: Adlai Holler <adlai@google.com>
Commit-Queue: Robert Phillips <robertphillips@google.com>
4 files changed