Set NACKed packet to -1 in TestNackRetransmission.

Zero is a valid sequence number which may occur even if there are no
retransmissions, this caused the test to flake as an incoming packet
would be mistaken for a retransmission.

BUG=2830
R=stefan@webrtc.org

Review URL: https://webrtc-codereview.appspot.com/7509005

git-svn-id: http://webrtc.googlecode.com/svn/trunk/webrtc@5417 4adac7df-926f-26a2-2b94-8c16560cd09d
1 file changed