decoder: increase intermediate bitstream buffer size

Earlier, the size for the intermediate bitstream buffer was
hard-coded creating the possibility of buffer overflows in case
of large data. This has been resolved by defining this buffer size' based on max height and max width.

Bug: oss-fuzz:56898
Bug: 273291708
Test: mpeg2_dec_fuzzer
(cherry picked from https://partner-android-review.googlesource.com/q/commit:3a10c1f25185b5427e478454d73ded7b3bcac94a)
(cherry picked from https://googleplex-android-review.googlesource.com/q/commit:3cb820f35397cd9ebfd49030004994a63e48f59b)
Merged-In: Ifc8cbbdf46ced7dc1586798be111ef6729d0d808
Change-Id: Ifc8cbbdf46ced7dc1586798be111ef6729d0d808
1 file changed