Simplify makeOps API

The index API are no longer needed now that the Geometries
hold pointers instead of indexes.

Change-Id: I940520816ca58959f2c7c415a8f356ea5bf3d293
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/255816
Commit-Queue: Herb Derby <herb@google.com>
Reviewed-by: Mike Klein <mtklein@google.com>
3 files changed