Merge "Prevent NPE while finishing activity" into rvc-dev am: 1dbee3e34b am: 3884ae8712 am: 04dfbf4d61 am: f8b17cd22c

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/11788494

Change-Id: Ic5e559d8487fae352974b7bf57bec93812963a28