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27691135  Remove transitional GN code.
426a2a51  Add avcodec_descriptor_next to sigs file.

TBR=dalecurtis@chromium.org

Review URL: https://codereview.chromium.org/1347253002

Cr-Commit-Position: 972c6d2dc6dd5efdad1377c0d224e03eb8f276f7@{#349257}

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