external/libgav1: backport obu parser fix | DO NOT MERGE cl/289910031: obu: Check for size validity in SetTileDataOffset Bug: b/147231862 Bug: b/147234020 Test: upstream test vectors, repro test case Change-Id: I440657926b7f763484b120b76579874fb7925dca (cherry picked from commit fd25597065d1eb70af61ef48dae263acbfca5303)