Make GrDrawVerticesOp a non-legacy GrMeshDrawOp

Change-Id: I0e1e6815ed41764115bc84a5967b3da3be4ce147
Reviewed-on: https://skia-review.googlesource.com/22722
Commit-Queue: Brian Salomon <bsalomon@google.com>
Reviewed-by: Greg Daniel <egdaniel@google.com>
4 files changed