Prevent the infinite boot-looping.

- When the device is already previsioned, just exiting itself will cause
  the boot-loop, because the Activity is re-triggered as HOME.
- If the case, remove itself to prevent from the boot-loop.

Bug: 249501464
Test: build sdk_emu_x86_64 and check if it boots successfully.
Change-Id: I19b11b8f389f9a47d6885a604d5a7c59b4665a26
1 file changed