Merge "Block relayout during transition to desktop" into udc-dev am: 3be325fb am: b508baa0

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



Change-Id: I44e6383f0abb62743e1fa5d9adb997a6032f3ee6
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>