Merge "Update dismiss appearance and add scrim per UX mocks." into rvc-dev am:...

Merge "Update dismiss appearance and add scrim per UX mocks." into rvc-dev am: a65d7258 am: 81d8cabe am: fc14e59c am: afbb4e1c

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/11683086

Change-Id: I768761a890f7d9c442dd80b7c808ecbfe26a5417