Reland "libsnapshot_fuzzer: Add tests"

This reverts commit 254b9046f70b324cca75857b7bddd12908ade81b.

Reason for revert: test fixed

Bug: 156689792
Test: run it then reboot

Change-Id: I33603e87b8f6b06fed2d18066ee5f00cdf45a52e
4 files changed