Add @GuardedBy annotation to PersistentDataBlockService#mIsWritable. am: 71d2a41dd9 am: d0339c6e8f am: 6aa436bef2 am: 76ca2da7e8 am: 0cc0219089 am: ced5ab190c am: 3cc7f6acdc am: e426dac4e2 am: b75b025578
am: 3ad5df5231

Change-Id: I9c159162e18af0820c76d42c22e2ec001ab72c62