Only report the first rtp packet because it indicates the media has started flowing.
BUG=
R=juberti@webrtc.org

Review URL: https://webrtc-codereview.appspot.com/37829004

Cr-Commit-Position: refs/heads/master@{#8189}
git-svn-id: http://webrtc.googlecode.com/svn/trunk@8189 4adac7df-926f-26a2-2b94-8c16560cd09d

talk/session/media/channel.cc

diff --git a/talk/session/media/channel.cc b/talk/session/media/channel.cc
index dbcdbb0..b47676e 100644
--- a/talk/session/media/channel.cc
+++ b/talk/session/media/channel.cc
@@ -554,7 +554,9 @@
     return;
   }
 
-  if (!has_received_packet_) {
+  // We are only interested in the first rtp packet because that
+  // indicates the media has started flowing.
+  if (!has_received_packet_ && !rtcp) {
     has_received_packet_ = true;
     signaling_thread()->Post(this, MSG_FIRSTPACKETRECEIVED);
   }