Merge "Check null for top activity when updating orientation" into tm-qpr-dev am: fc18585969 am: 90b8a49013

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/21218459

Change-Id: I01d6cf719f3c9df4de2370b9b6af801399588c67
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>