Use snapshot value sys.fuse_snapshot instead of persist.sys.fuse

This will allow us to receive values from server flags and store them in
persist.sys.fuse without risking flag consistency during a boot.

Test: manual - flip persist.sys.fuse both ways and make sure FuseDaemon
works as expected.
Bug: 140803239

Change-Id: I839a1973c98b4eda982226d20be48d1c08e7464a
4 files changed