Merge "libutils: check vsnprintf error" into oc-dev am: a03d37d542 am: d8801aaad8 am: d05ecb8d9d am: dc99a094dd am: 64b312bbd8

Original change: https://googleplex-android-review.googlesource.com/c/platform/system/core/+/12254459

Change-Id: I7d40bc3c63aa13c4050662f17b8a0854f8864ce4