Merge "Skip null surface when validating transition" into udc-dev am:...

Merge "Skip null surface when validating transition" into udc-dev am: 4bc363b9 am: d87a7fb1 am: ef8d0fc2

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/23765883



Change-Id: I905f53972280ab015b4d549d7b850fb0982f3a0b
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>