Look for the correct lock icon view.

It seems that the lock icon view controller is instantiated before the
view configurator removes the view.

If the migrate lock icon flag is off, findViewById in notification panel
view intead.

Fixes: 289133156
Test: view lock screen with MIGRATE_LOCK_ICON flag on and off.
Change-Id: I0a79ac21228c7e954606cf5e2820d070d80271d0