SkColorSpacePrimaries: Add operator== Bug: 40044808 Change-Id: I803579b5d7ad08e35dd70cac1e706c089e980d55 Reviewed-on: https://skia-review.googlesource.com/c/skia/+/1142597 Commit-Queue: Christopher Cameron <ccameron@google.com> Reviewed-by: Christopher Cameron <ccameron@google.com> Reviewed-by: Robert Phillips <robertphillips@google.com>