Initialized unitialized variables. am: 3e881aa30f am: 7dcdeaa0ac am: 7949cffd70

Original change: https://android-review.googlesource.com/c/platform/system/update_engine/+/2209803

Change-Id: I38ec0a57731a67ce200369debdff7697642b80ac
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>