add poly_tf to skcms_sRGB_profile

And a unit test that makes sure it's kept up to date,
and that skcms_OptimizeForSpeed() is a no-op when the
has_poly_tf bits are already set.

Change-Id: I5bf982084c312cafe59fb7a9d21918ccabec6f3d
Reviewed-on: https://skia-review.googlesource.com/123928
Commit-Queue: Brian Osman <brianosman@google.com>
Reviewed-by: Brian Osman <brianosman@google.com>
Auto-Submit: Mike Klein <mtklein@google.com>
3 files changed