Merge "Create test app to emulate assistant UI." into tm-qpr-dev am: 4e330bd3fc am: 1d45f10c70

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

Change-Id: Ibb49b564cab16af899e0c0f6069eab941ada79a9
Signed-off-by: Automerger Merge Worker <[email protected]>