[1/2] base: expandable volume panel and tweaks

* Ditch aosp volume panel and use expandable as default, hardcode it.
* Add VOLUME_LINK_NOTIFICATION option to allow adjusting notification
  and ringer separately (default=1).
* Add VOLUME_ADJUST_SOUNDS_ENABLED option to allow disabling
  the volume adjust sound (default=1).
* Replace old Settings slider icon with new KitKat cog icon

Signed-off-by: Ricky Salinas <rsalinas1@mail.usf.edu>
Signed-off-by: Carlo Savignano <stevewatersy@gmail.com>

Change-Id: I94e0f944f76ee9751663de8ac40d99a342884259
Volume Rocker: Hardcode music track seek option (1/2).

* The feature is enabled by default but not configurable.

Signed-off-by: Carlo Savignano <stevewatersy@gmail.com>

PS2:

* Remove unneeded variables.

Signed-off-by: Carlo Savignano <stevewatersy@gmail.com>

Change-Id: I0c72dd00f8a161255a59330862fa69c66735a3e4