Add video send bitrates to histogram stats:

- total bitrate ("WebRTC.Video.BitrateSentInKbps")
- media bitrate ("WebRTC.Video.MediaBitrateSentInKbps")
- rtx bitrate ("WebRTC.Video.RtxBitrateSentInKbps")
- padding bitrate ("WebRTC.Video.PaddingBitrateSentInKbps")
- retransmitted bitrate ("WebRTC.Video.RetransmittedBitrateInKbps")

Add retransmitted bytes to StreamDataCounters.

Change in UpdateRtpStats to also update counters for retransmitted packet.

BUG=crbug/419657
R=mflodman@webrtc.org, stefan@webrtc.org

Review URL: https://webrtc-codereview.appspot.com/30199004

git-svn-id: http://webrtc.googlecode.com/svn/trunk@7838 4adac7df-926f-26a2-2b94-8c16560cd09d

webrtc/modules/rtp_rtcp/source/rtp_rtcp_impl.h

@@ -177,6 +177,10 @@ class ModuleRtpRtcpImpl : public RtpRtcp {
   virtual int32_t DataCountersRTP(size_t* bytes_sent,
                                   uint32_t* packets_sent) const OVERRIDE;
 
+  virtual void GetSendStreamDataCounters(
+      StreamDataCounters* rtp_counters,
+      StreamDataCounters* rtx_counters) const OVERRIDE;
+
   // Get received RTCP report, sender info.
   virtual int32_t RemoteRTCPStat(RTCPSenderInfo* sender_info) OVERRIDE;