(This is a merge of http://go/wvgerrit/51084)
Nominally, OEMCrypto probably shouldn't modify the buffer descriptor we
pass into OEMCrypto_DecryptCENC(), but in practice, we know some
platforms do this, so we make defensive copies in
CryptoSession::DecryptInChunks() just in case. Turns out, some devices
also behave like this in OEMCrypto_CopyBuffer(), so we should also be
doing defensive copies in CryptoSession::CopyBufferInChunks().
Bug: 79779554
Test: ExoPlayer Demo App, played "Secure Subsample UHD (WebM, VP9)"
Test: build_and_run_all_unit_tests.sh
Change-Id: Ib46043a6cc0aa42d1d1cc85f5adb477c566363e9
b305d99d3b