Merge "Tune stillness detector for more responsive headtracking" into tm-qpr-dev am: 6500251489 am: 6cbac685c3

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/av/+/19754594

Change-Id: I050cce34c2b9b79eb2bd6286ace7fab64e8516a3
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>