WebRTCDemo: clean the error message due to API clean up and add ability to route the audio through all three outputs, headset/earpiece/loudspeaker

BUG=3366
TEST=Manual Test
R=fischman@webrtc.org

Review URL: https://webrtc-codereview.appspot.com/17559004

git-svn-id: http://webrtc.googlecode.com/svn/trunk@6207 4adac7df-926f-26a2-2b94-8c16560cd09d