Settings: Move HALO Blacklist checkbox to Blacklist

Change-Id: I25641f62cba9bc6e7fea45de239467988db6da04
Blacklist: Avoid crash when dialog dismissed via back button.
A user usually presses the back button only
when he/she does not want the changes to be saved.
Hence we need to revert the changes that took place
when the dialog is dismissed with back button.

Change-Id: Ied22f8932dbecfe9640798e8cf10172b18f4b08c