Postpone call to postEnroll() until we actually leave activity.

The existing code was calling postEnroll() too soon, which resulted
in the inability to add more than one fingerprint. The solution is to
only call postEnroll() when we're leaving the activity.

Fixes bug 22438498

Change-Id: Ia134899e12b4edc9cced834e99cb2bfd2d51321f
1 file changed