installd: Add destroyAppDataSnapshot and corresponding binder API

- destroyAppDataSnapshot: deletes both ce and de snapshots (controlled
  via storageFlags), for ce snapshot fallbacks to deleting it by it's
  inode in case snapshot is not accessible (user hasn't unlocked the
  phone yet).
- snapshotAppData: in case ce snapshot was requested, it will now return
  inode if a folder with the snapshot. Otherwise it will return 0.

Passing ceSnapshotInode to destroyAppDataSnapshot should make logic
inside RollbackManagerService a bit easier. Since it will be able to
delete ce snapshot regardless of user unlocking their phone.

Bug: 112431924
Test: installd_service_test installd_utils_test
Change-Id: I015de12593b87f3000f004cc0a901a9208d0b693
Merged-In: I015de12593b87f3000f004cc0a901a9208d0b693