Fix audio volume issues and remove dead code

There was some extraneous code left over from the AppRTCDemo that was
causing some problems.

1) There was a block setting a wakelock for no good reason

2) A second block changed some settings in the audio manager. These had
the side effect of messing up the client phone's volume settings semi-
permanently (at least until reboot or the app was uninstalled).

Both sections are removed.

Change-Id: I60ce9c099a333d5d67f971336bf58d0cd0f5254b