Merge "Fix race b/w prepareInitialInputBuffers and...

Merge "Fix race b/w  prepareInitialInputBuffers and feedInputBuffersIfAvailable" into udc-dev am: 9f896f2f am: ea5c1ed3 am: 701a687c am: 395cb3f5

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/av/+/22914549



Change-Id: I784c985458ff2f4b03b59569d72f07984b5555fe
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>