storaged: protect global proto_loaded am: 4d3fe5ab72 am: 96c38ce6a2 am: 655c48c89d

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

Change-Id: I2e39cc56d9255d14825a71f3b2126836e303fcd0