WebRTCDemo: Enable making multiple calls.
Previously after the first call subsequent attempts to bind the RTP/RTCP ports would fail, since r3754.

BUG=1618

Review URL: https://webrtc-codereview.appspot.com/1302007

git-svn-id: http://webrtc.googlecode.com/svn/trunk/webrtc@3817 4adac7df-926f-26a2-2b94-8c16560cd09d
5 files changed