tree b0e01c4d5404738427aa7ec4ea30901490b56e9b
parent 94c4f41ab8d5ad7226ee796a1ecbb95d6874a75f
author Florin Malita <fmalita@chromium.org> 1533850154 -0400
committer Skia Commit-Bot <skia-commit-bot@chromium.org> 1533852332 +0000

[skottie] Avoid UB while parsing 1-based indices

Current impl can underflow int due to unchecked arithmetic.

Add a Parse<size_t> specialization and convert call sites which use
inline arithmetic.  Underflowing unsigned types should be well defined
and caught in later tests.

Bug: oss-fuzz:9798
Change-Id: Iaebe8aad4009e2511fe1d8733d336f5f119bb384
Reviewed-on: https://skia-review.googlesource.com/146648
Reviewed-by: Kevin Lubick <kjlubick@google.com>
Commit-Queue: Florin Malita <fmalita@chromium.org>