Merge "Promote isFloating to TestApi" into tm-dev am: 6ed3a87798 am: 7d7068b9fa

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/17887364

Change-Id: I367cd92e949564121a945278a82f7dec70c08fdd
Ignore-AOSP-First: this is an automerge
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>