Merge "Update letterbox restart dialog style to match other Android U dialogs"...

Merge "Update letterbox restart dialog style to match other Android U dialogs" into udc-dev am: 565b8127

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/23561836



Change-Id: I803d068538a5e0090886639e366e617e7e702cb7
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>