This is completely unused - GrMatrixEffect is the only thing that deals
with matrix transforms on child sampling. Removing this makes everything
simpler to reason about.
Change-Id: I555a3fd937c064f2480b149a6d4d8e36f7ee69bc
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/402176
Commit-Queue: Brian Osman <brianosman@google.com>
Reviewed-by: Michael Ludwig <michaelludwig@google.com>
Reviewed-by: Brian Salomon <bsalomon@google.com>
