Merge "Letterbox Reacheability Multiplier Persistence" into tm-qpr-dev am: a8117a57

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/19429915



Change-Id: I8949d6f923a335d88e49e84848bec7992084f1e1
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>