DO NOT MERGE Fix divide by zero

and be stricter about the layout of various boxes in mp4 files.

Bug: 31318219
Change-Id: I50034d5b6b1967ca6e88aabeacf49f26ba3c0d32
(cherry picked from commit 2e211d38a3124849ef46376256d01e69549c422f)
1 file changed