opts.gypi -> opts.gni

BUG=skia:

GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=4026

Change-Id: Ib687bd7ce87ddbbc60f95e7a30e20575971e5c59
Reviewed-on: https://skia-review.googlesource.com/4026
Reviewed-by: Ben Wagner <bungeman@google.com>
Commit-Queue: Mike Klein <mtklein@chromium.org>
4 files changed