Merge "Nest SystemUI alert dialogs in NestedScrollLayout" into tm-dev am: ea91f5bb91 am: fdf53ba01f am: b1b78ca2a3

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/17756832

Change-Id: I28513bb035e6366b3a46f63a58a518ca013678dd
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>