Merge "Workaround a robelectric related NPE in SurfaceSyncGroup.addTimer" into udc-dev am: a380a318d3

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/23454315

Change-Id: I9146b5c4f0449ff64f9217ff5e0dc9afdcf2ed9a
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>