Forward the result in the enrolling screen from the finish screen,
so that if the user presses back in "Add another" after enrolling
the first fingerprint, it will return RESULT_CANCELED instead of
RESULT_FINISHED, and go back to find sensor screen.
This results in the following behavioral changes:
- RESULT_FINISHED will only be sent if the user presses "Done" in
FingerprintEnrollFinish. If the user clicks back in
FingerprintEnrollEnrolling, they will always go back to the
previous screen with RESULT_CANCELED, which would either be
FindSensor or FingerprintSettings.
- If the user presses back in FingerprintEnrollFinish, which is only
possible outside of Setup Wizard, they will be back in Find Sensor,
and pressing next will enroll an additional fingerprint.
- Edge case: if the user enrolled the maximum number of
fingerprints, and presses back, they will be bounced all the way
back to Settings > Security.
Bug: 22552741
Change-Id: Ifc5e8a9150491b4303e01ebd0fc17b6d39dd372d
