Fix/sim usim problems

Mmmm, I can't exactly remember why this has been coded this way, but i guess it won't end in an StaleElementException, due to the return statement in line 726. If it happens to be that enable != current, the flow will continue without tapping the "sim_security" element before, so at line 728, it'll be the first time.

I'm not sure i got what you were trying to say anyway.