storaged: protect global proto_loaded am: 4d3fe5ab am: 96c38ce6 am: 7fa827fd am: df566bb9 am: 7332141d

Original change: https://googleplex-android-review.googlesource.com/c/platform/system/core/+/13112711

Change-Id: Ic21ca332b2382da9eec5d5f09b554659adc3dca5