fix: enabling/disabling "Flip tiles"

-Not sure exactly which change fixed this...

-OnPreferenceChanged* wasn't hooked up

-Normalized content resolver usage

-Normalized use of "newvalue" onpreferencechanged*

-Change fliptiles setting init to use default "enabled"
to match SystemUI

-NOTE: There was no error to go off of but when you changed
the value, it wasn't making it into the database..

Change-Id: Ida073ce97d11a54a71e9cc13a986ca677329362d