Merge "C2SoftAvcDec: keep threads active for entire sequence" into main am: 4d3bc10216

Original change: https://android-review.googlesource.com/c/platform/frameworks/av/+/2899228

Change-Id: Idfca02d0b13bec2859b3e641c2849db7eaea4add
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>