Make SmallPathOp a non-legacy GrMeshDrawOp

Change-Id: I7fd0739d7bae9176e816772b3aed54528c4fa576
Reviewed-on: https://skia-review.googlesource.com/21865
Commit-Queue: Brian Salomon <bsalomon@google.com>
Reviewed-by: Jim Van Verth <jvanverth@google.com>
3 files changed