Merge "Only check letterbox position in book mode" into tm-qpr-dev am:...

Merge "Only check letterbox position in book mode" into tm-qpr-dev am: edc5058b am: ef53043c am: ca7d53d8 am: bad12f0f

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/22251403



Change-Id: I29edf779aac708ec3c58b003ec584be1c3e23b34
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>