Bugfix : Expanded volume overlay

If you switch to the Expanded volume overlay
(Settings > Sound > Volume panel)
from any of the other settings that are not expanded
then the Expanded overlay appears collapsed.

The only way to make it appear expanded is to restart the framework
or
In the Expandable view - expand the volumes - then immediately change.

This patch fixes this and also has a slight improvement in the
case where a user selects the same choice they have already.

Change-Id: I9264ce62e239f497e0a2924c6769f066f196ebeb