[skottie] Fix skottie2movie after async API change

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Change-Id: I4793d3540f3b5f5fa06ce7a3d1ce2a281660fb72
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/251255
Reviewed-by: Florin Malita <fmalita@chromium.org>
Commit-Queue: Florin Malita <fmalita@chromium.org>
1 file changed