Merge "Block relayout during transition to desktop" into udc-dev am: 3be325fb64

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/22298053

Change-Id: I8ff9978a96c8566101ab9b8207e9152c09ae9127
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>