Add Timestamp Validation in MPEG4Writer

Validate the timestamps of the input buffers to prevent overflow and
underflow errors.

Test: mpeg4_writer_fuzzer
Test: atest android.media.muxer.cts.MediaMuxerTest
Test: atest CtsMediaV2TestCases:MuxerUnitTest
Bug: 182649641

Change-Id: I00539d92dfe860e7abb79d96dbf3ee70c9762ee5
2 files changed