AlertSlider: refactor to reflect slider state

As there is the possibility of having more option values
for the alertslider (such as various zen mode states)
in addition to the current ringer mode states,
update logic to reflect the value slider's position is
set to instead of the ringer state we were using before.

Change-Id: I086549c8fbcbcc213b2964dca8d7979fcb64932b
2 files changed