Merge "Create test app to emulate assistant UI." into tm-qpr-dev am: 4e330bd3fc

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/19928112

Change-Id: I531ec78cc1df6a5bacd205afc48f39f2f1d26048
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>